Support dyanmically setting key request headers

Issue: #1924

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=146120465

demo/src/main/java/com/google/android/exoplayer2/demo/PlayerActivity.java

@@ -70,8 +70,6 @@ import com.google.android.exoplayer2.util.Util;
 import java.net.CookieHandler;
 import java.net.CookieManager;
 import java.net.CookiePolicy;
-import java.util.HashMap;
-import java.util.Map;
 import java.util.UUID;
 
 /**
@@ -239,19 +237,9 @@ public class PlayerActivity extends Activity implements OnClickListener, ExoPlay
       if (drmSchemeUuid != null) {
         String drmLicenseUrl = intent.getStringExtra(DRM_LICENSE_URL);
         String[] keyRequestPropertiesArray = intent.getStringArrayExtra(DRM_KEY_REQUEST_PROPERTIES);
-        Map<String, String> keyRequestProperties;
-        if (keyRequestPropertiesArray == null || keyRequestPropertiesArray.length < 2) {
-          keyRequestProperties = null;
-        } else {
-          keyRequestProperties = new HashMap<>();
-          for (int i = 0; i < keyRequestPropertiesArray.length - 1; i += 2) {
-            keyRequestProperties.put(keyRequestPropertiesArray[i],
-                keyRequestPropertiesArray[i + 1]);
-          }
-        }
         try {
           drmSessionManager = buildDrmSessionManager(drmSchemeUuid, drmLicenseUrl,
-              keyRequestProperties);
+              keyRequestPropertiesArray);
         } catch (UnsupportedDrmException e) {
           int errorStringId = Util.SDK_INT < 18 ? R.string.error_drm_not_supported
               : (e.reason == UnsupportedDrmException.REASON_UNSUPPORTED_SCHEME
@@ -349,12 +337,18 @@ public class PlayerActivity extends Activity implements OnClickListener, ExoPlay
   }
 
   private DrmSessionManager<FrameworkMediaCrypto> buildDrmSessionManager(UUID uuid,
-      String licenseUrl, Map<String, String> keyRequestProperties) throws UnsupportedDrmException {
+      String licenseUrl, String[] keyRequestPropertiesArray) throws UnsupportedDrmException {
     if (Util.SDK_INT < 18) {
       return null;
     }
     HttpMediaDrmCallback drmCallback = new HttpMediaDrmCallback(licenseUrl,
-        buildHttpDataSourceFactory(false), keyRequestProperties);
+        buildHttpDataSourceFactory(false));
+    if (keyRequestPropertiesArray != null) {
+      for (int i = 0; i < keyRequestPropertiesArray.length - 1; i += 2) {
+        drmCallback.setKeyRequestProperty(keyRequestPropertiesArray[i],
+            keyRequestPropertiesArray[i + 1]);
+      }
+    }
     return new DefaultDrmSessionManager<>(uuid,
         FrameworkMediaDrm.newInstance(uuid), drmCallback, null, mainHandler, eventLogger);
   }

library/src/main/java/com/google/android/exoplayer2/drm/HttpMediaDrmCallback.java

@@ -24,6 +24,8 @@ import com.google.android.exoplayer2.drm.ExoMediaDrm.ProvisionRequest;
 import com.google.android.exoplayer2.upstream.DataSourceInputStream;
 import com.google.android.exoplayer2.upstream.DataSpec;
 import com.google.android.exoplayer2.upstream.HttpDataSource;
+import com.google.android.exoplayer2.upstream.HttpDataSource.Factory;
+import com.google.android.exoplayer2.util.Assertions;
 import com.google.android.exoplayer2.util.Util;
 import java.io.IOException;
 import java.util.HashMap;
@@ -57,21 +59,62 @@ public final class HttpMediaDrmCallback implements MediaDrmCallback {
   }
 
   /**
+   * @deprecated Use {@link HttpMediaDrmCallback#HttpMediaDrmCallback(String, Factory)}. Request
+   *     properties can be set by calling {@link #setKeyRequestProperty(String, String)}.
    * @param defaultUrl The default license URL.
    * @param dataSourceFactory A factory from which to obtain {@link HttpDataSource} instances.
    * @param keyRequestProperties Request properties to set when making key requests, or null.
    */
+  @Deprecated
   public HttpMediaDrmCallback(String defaultUrl, HttpDataSource.Factory dataSourceFactory,
       Map<String, String> keyRequestProperties) {
     this.dataSourceFactory = dataSourceFactory;
     this.defaultUrl = defaultUrl;
-    this.keyRequestProperties = keyRequestProperties;
+    this.keyRequestProperties = new HashMap<>();
+    if (keyRequestProperties != null) {
+      this.keyRequestProperties.putAll(keyRequestProperties);
+    }
+  }
+
+  /**
+   * Sets a header for key requests made by the callback.
+   *
+   * @param name The name of the header field.
+   * @param value The value of the field.
+   */
+  public void setKeyRequestProperty(String name, String value) {
+    Assertions.checkNotNull(name);
+    Assertions.checkNotNull(value);
+    synchronized (keyRequestProperties) {
+      keyRequestProperties.put(name, value);
+    }
+  }
+
+  /**
+   * Clears a header for key requests made by the callback.
+   *
+   * @param name The name of the header field.
+   */
+  public void clearKeyRequestProperty(String name) {
+    Assertions.checkNotNull(name);
+    synchronized (keyRequestProperties) {
+      keyRequestProperties.remove(name);
+    }
+  }
+
+  /**
+   * Clears all headers for key requests made by the callback.
+   */
+  public void clearAllKeyRequestProperties() {
+    synchronized (keyRequestProperties) {
+      keyRequestProperties.clear();
+    }
   }
 
   @Override
   public byte[] executeProvisionRequest(UUID uuid, ProvisionRequest request) throws IOException {
     String url = request.getDefaultUrl() + "&signedRequest=" + new String(request.getData());
-    return executePost(url, new byte[0], null);
+    return executePost(dataSourceFactory, url, new byte[0], null);
   }
 
   @Override
@@ -85,14 +128,14 @@ public final class HttpMediaDrmCallback implements MediaDrmCallback {
     if (C.PLAYREADY_UUID.equals(uuid)) {
       requestProperties.putAll(PLAYREADY_KEY_REQUEST_PROPERTIES);
     }
-    if (keyRequestProperties != null) {
+    synchronized (keyRequestProperties) {
       requestProperties.putAll(keyRequestProperties);
     }
-    return executePost(url, request.getData(), requestProperties);
+    return executePost(dataSourceFactory, url, request.getData(), requestProperties);
   }
 
-  private byte[] executePost(String url, byte[] data, Map<String, String> requestProperties)
-      throws IOException {
+  private static byte[] executePost(HttpDataSource.Factory dataSourceFactory, String url,
+      byte[] data, Map<String, String> requestProperties) throws IOException {
     HttpDataSource dataSource = dataSourceFactory.createDataSource();
     if (requestProperties != null) {
       for (Map.Entry<String, String> requestProperty : requestProperties.entrySet()) {

library/src/main/java/com/google/android/exoplayer2/drm/OfflineLicenseHelper.java

@@ -93,7 +93,7 @@ public final class OfflineLicenseHelper<T extends ExoMediaCrypto> {
   public static OfflineLicenseHelper<FrameworkMediaCrypto> newWidevineInstance(
       String licenseUrl, Factory httpDataSourceFactory) throws UnsupportedDrmException {
     return newWidevineInstance(
-        new HttpMediaDrmCallback(licenseUrl, httpDataSourceFactory, null), null);
+        new HttpMediaDrmCallback(licenseUrl, httpDataSourceFactory), null);
   }
 
   /**

library/src/main/java/com/google/android/exoplayer2/upstream/HttpDataSource.java

@@ -41,8 +41,8 @@ public interface HttpDataSource extends DataSource {
     HttpDataSource createDataSource();
 
     /**
-     * Sets a default request header field for {@link HttpDataSource} instances subsequently
-     * created by the factory. Previously created instances are not affected.
+     * Sets a default request header for {@link HttpDataSource} instances subsequently created by
+     * the factory. Previously created instances are not affected.
      *
      * @param name The name of the header field.
      * @param value The value of the field.
@@ -50,16 +50,16 @@ public interface HttpDataSource extends DataSource {
     void setDefaultRequestProperty(String name, String value);
 
     /**
-     * Clears a default request header field for {@link HttpDataSource} instances subsequently
-     * created by the factory. Previously created instances are not affected.
+     * Clears a default request header for {@link HttpDataSource} instances subsequently created by
+     * the factory. Previously created instances are not affected.
      *
      * @param name The name of the header field.
      */
     void clearDefaultRequestProperty(String name);
 
     /**
-     * Clears all default request header fields for all {@link HttpDataSource} instances
-     * subsequently created by the factory.  Previously created instances are not affected.
+     * Clears all default request header for all {@link HttpDataSource} instances subsequently
+     * created by the factory.  Previously created instances are not affected.
      */
     void clearAllDefaultRequestProperties();
 
@@ -232,7 +232,7 @@ public interface HttpDataSource extends DataSource {
   int read(byte[] buffer, int offset, int readLength) throws HttpDataSourceException;
 
   /**
-   * Sets the value of a request header field. The value will be used for subsequent connections
+   * Sets the value of a request header. The value will be used for subsequent connections
    * established by the source.
    *
    * @param name The name of the header field.
@@ -241,7 +241,7 @@ public interface HttpDataSource extends DataSource {
   void setRequestProperty(String name, String value);
 
   /**
-   * Clears the value of a request header field. The change will apply to subsequent connections
+   * Clears the value of a request header. The change will apply to subsequent connections
    * established by the source.
    *
    * @param name The name of the header field.
@@ -249,7 +249,7 @@ public interface HttpDataSource extends DataSource {
   void clearRequestProperty(String name);
 
   /**
-   * Clears all request header fields that were set by {@link #setRequestProperty(String, String)}.
+   * Clears all request headers that were set by {@link #setRequestProperty(String, String)}.
    */
   void clearAllRequestProperties();