media: Set MediaClientAndroid in the GPU process.

content/public/common/content_client.cc

Index: content/public/common/content_client.cc
diff --git a/content/public/common/content_client.cc b/content/public/common/content_client.cc
index 087d8b788049e11d8165286902945681877874e3..0c6a8b2afd0ad811f9555e64f24ca086f3a8e49b 100644
--- a/content/public/common/content_client.cc
+++ b/content/public/common/content_client.cc
@@ -123,4 +123,10 @@ base::StringPiece ContentClient::GetOriginTrialPublicKey() {
   return base::StringPiece();
 }
 
+#if defined(OS_ANDROID)
+media::MediaClientAndroid* ContentClient::GetMediaClientAndroid() {
+  return nullptr;
+}
+#endif  // OS_ANDROID
+
 }  // namespace content