Fix a few GVR 360 nits

- Remove unused TAG
- android.Theme.Material can only be used from API level 21
- Rm "Base" from activity name for consistency

PiperOrigin-RevId: 233410603

extensions/gvr/src/main/java/com/google/android/exoplayer2/ext/gvr/GvrPlayerActivity.java

@@ -50,9 +50,8 @@ import com.google.vr.sdk.controller.ControllerManager;
 import javax.microedition.khronos.egl.EGLConfig;
 import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
 
-/** VR 360 video player base activity class. */
+/** Base activity for VR 360 video playback. */
-public abstract class BaseGvrPlayerActivity extends GvrActivity {
+public abstract class GvrPlayerActivity extends GvrActivity {
-  private static final String TAG = "GvrPlayerActivity";
 
   private static final int EXIT_FROM_VR_REQUEST_CODE = 42;
 
@@ -66,7 +65,7 @@ public abstract class BaseGvrPlayerActivity extends GvrActivity {
   @MonotonicNonNull private SceneRenderer scene;
   @MonotonicNonNull private PlayerControlView playerControl;
 
-  public BaseGvrPlayerActivity() {
+  public GvrPlayerActivity() {
     mainHandler = new Handler(Looper.getMainLooper());
   }
 
@@ -348,7 +347,7 @@ public abstract class BaseGvrPlayerActivity extends GvrActivity {
               }
             });
       } else if (!appButtonDown && controller.appButtonState) {
-        glView.post(BaseGvrPlayerActivity.this::togglePlayerControlVisibility);
+        glView.post(GvrPlayerActivity.this::togglePlayerControlVisibility);
       }
       appButtonDown = controller.appButtonState;
     }

extensions/gvr/src/main/res/values-v21/styles.xml

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2018 The Android Open Source Project
+
+     Licensed under the Apache License, Version 2.0 (the "License");
+     you may not use this file except in compliance with the License.
+     You may obtain a copy of the License at
+
+          http://www.apache.org/licenses/LICENSE-2.0
+
+     Unless required by applicable law or agreed to in writing, software
+     distributed under the License is distributed on an "AS IS" BASIS,
+     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+     See the License for the specific language governing permissions and
+     limitations under the License.
+-->
+<resources>
+  <style name="VrTheme" parent="android:Theme.Material"/>
+</resources>

extensions/gvr/src/main/res/values/styles.xml

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<!-- Copyright (C) 2018 The Android Open Source Project
+<!-- Copyright (C) 2019 The Android Open Source Project
 
      Licensed under the Apache License, Version 2.0 (the "License");
      you may not use this file except in compliance with the License.
@@ -13,7 +13,6 @@
      See the License for the specific language governing permissions and
      limitations under the License.
 -->
-<!-- Android Views rendered in VR should use a theme that matches the rest of the VR UI.-->
 <resources>
-  <style name="VrTheme" parent="android:Theme.Material"/>
+  <style name="VrTheme" parent="android:Theme.Holo"/>
 </resources>