Disable MediaSession API for WebView

android_webview/lib/main/aw_main_delegate.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "android_webview/lib/main/aw_main_delegate.h"
 
 #include <memory>
 
 #include "android_webview/browser/aw_content_browser_client.h"
 #include "android_webview/browser/browser_view_renderer.h"
@@ skipping 94 matching lines @@
   cl->AppendSwitch(switches::kEnableAggressiveDOMStorageFlushing);
 
   // Webview does not currently support the Presentation API, see
   // https://crbug.com/521319
   cl->AppendSwitch(switches::kDisablePresentationAPI);
 
   // WebView doesn't support Remote Playback API for the same reason as the
   // Presentation API, see https://crbug.com/521319.
   cl->AppendSwitch(switches::kDisableRemotePlaybackAPI);
 
+  // WebView does not support MediaSession API since there's no UI for media
+  // metadata and controls.
+  cl->AppendSwitchASCII(switches::kDisableBlinkFeatures, "MediaSession");

[Torne, 2017/01/09 11:47:06]

I'm not too familiar with how command line manipulation works; is it safe to
call AppendSwitch for kDisableBlinkFeatures multiple times with different
values? Do they all take effect?

[Zhiqiang Zhang (Slow), 2017/01/09 14:29:21]

You are right, they will conflict.
Now I just follow how RemotePlayback and Presentation does.

+
 #if defined(V8_USE_EXTERNAL_STARTUP_DATA)
   if (cl->GetSwitchValueASCII(switches::kProcessType).empty()) {
     // Browser process (no type specified).
 
     content::RegisterMediaUrlInterceptor(new AwMediaUrlInterceptor());
     BrowserViewRenderer::CalculateTileMemoryPolicy();
     // WebView apps can override WebView#computeScroll to achieve custom
     // scroll/fling. As a result, fling animations may not be ticked,
     // potentially
     // confusing the tap suppression controller. Simply disable it for WebView
@@ skipping 139 matching lines @@
 
 AwWebPreferencesPopulater* AwMainDelegate::CreateWebPreferencesPopulater() {
   return new AwWebPreferencesPopulaterImpl();
 }
 
 AwLocaleManager* AwMainDelegate::CreateAwLocaleManager() {
   return new AwLocaleManagerImpl();
 }
 
 }  // namespace android_webview