diff --git a/extensions/cast/build.gradle b/extensions/cast/build.gradle
index 253a1922a8..8780b961d6 100644
--- a/extensions/cast/build.gradle
+++ b/extensions/cast/build.gradle
@@ -21,7 +21,6 @@ android {
     defaultConfig {
         minSdkVersion 14
         targetSdkVersion project.ext.targetSdkVersion
-        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
     }
 }
 
diff --git a/extensions/cronet/build.gradle b/extensions/cronet/build.gradle
index 1cfb4f5513..0a52344464 100644
--- a/extensions/cronet/build.gradle
+++ b/extensions/cronet/build.gradle
@@ -21,7 +21,6 @@ android {
     defaultConfig {
         minSdkVersion project.ext.minSdkVersion
         targetSdkVersion project.ext.targetSdkVersion
-        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
     }
 
     sourceSets.main {