Enabling autoplay and fullscreen for downloaded media

chrome/browser/android/tab_android.cc

 // Copyright 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 "chrome/browser/android/tab_android.h"
 
 #include <stddef.h>
 
 #include "base/android/jni_android.h"
 #include "base/android/jni_string.h"
@@ skipping 55 matching lines @@
 #include "content/public/browser/interstitial_page.h"
 #include "content/public/browser/navigation_entry.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/render_frame_host.h"
 #include "content/public/browser/render_process_host.h"
 #include "content/public/browser/render_view_host.h"
 #include "content/public/browser/user_metrics.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/common/browser_controls_state.h"
 #include "content/public/common/resource_request_body.h"
+#include "content/public/common/web_preferences.h"
 #include "jni/Tab_jni.h"
 #include "net/base/escape.h"
 #include "skia/ext/image_operations.h"
 #include "third_party/WebKit/public/platform/WebReferrerPolicy.h"
 #include "ui/android/view_android.h"
 #include "ui/android/window_android.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/base/window_open_disposition.h"
 #include "ui/display/display.h"
 #include "ui/display/screen.h"
@@ skipping 623 matching lines @@
       env, *offline_page);
 }
 
 bool TabAndroid::HasPrerenderedUrl(JNIEnv* env,
                                    const JavaParamRef<jobject>& obj,
                                    const JavaParamRef<jstring>& url) {
   GURL gurl(base::android::ConvertJavaStringToUTF8(env, url));
   return HasPrerenderedUrl(gurl);
 }
 
+void TabAndroid::ConfigureEmbeddedMediaExperience(
+    JNIEnv* env,
+    const base::android::JavaParamRef<jobject>& obj) {
+  content::RenderViewHost* host = web_contents()->GetRenderViewHost();
+  if (!host)
+    return;
+
+  content::WebPreferences prefs = host->GetWebkitPreferences();
+  prefs.user_gesture_required_for_media_playback = false;

[mlamouri (slow - plz ping), 2017/02/17 10:01:43]

Is it needed? Can't you simply autoplay from C++ to avoid worrying about this?

[shaktisahu, 2017/02/17 19:18:06]

Done. Thanks!

+  prefs.embedded_media_experience_enabled = true;
+  host->UpdateWebkitPreferences(prefs);

[mlamouri (slow - plz ping), 2017/02/17 10:01:43]

That does not sound correct because if any one calls UpdateWebkitPreferences
later, your settings will be disabled. Instead, you should make sure that when
the settings are refreshed, it checks for the Tab's information.

[shaktisahu, 2017/02/17 19:18:06]

I looked around and didn't find any function that does it differently.
Whoever wants to set prefs, they first call GetWebkitPreferences to get the
existing prefs and add their preferences to it. So, unless someone wants to
specifically update embedded_media_experience_enabled, it should't be an issue.

[mlamouri (slow - plz ping), 2017/02/20 11:31:50]

The issue is that you are calling UpdateWebkitPreferences with the value set to
true but any one calling this later will revert your setting. The expectation is
that UpdateWebkitPreferences will have the logic that checks for the value. You
can look at |media_playback_gesture_whitelist_scope| for an example.

[shaktisahu, 2017/02/21 07:02:56]

Done.
Thanks! I think this is especially useful for the situation where the current
RenderViewHost or even WebContents is swapped for a new one, and we still get
our preference set correctly.

+}
+
 namespace {
 
 class ChromeInterceptNavigationDelegate : public InterceptNavigationDelegate {
  public:
   ChromeInterceptNavigationDelegate(JNIEnv* env, jobject jdelegate)
       : InterceptNavigationDelegate(env, jdelegate) {}
 
   bool ShouldIgnoreNavigation(
       const NavigationParams& navigation_params) override {
     NavigationParams chrome_navigation_params(navigation_params);
@@ skipping 35 matching lines @@
 static void Init(JNIEnv* env, const JavaParamRef<jobject>& obj) {
   TRACE_EVENT0("native", "TabAndroid::Init");
   // This will automatically bind to the Java object and pass ownership there.
   new TabAndroid(env, obj);
 }
 
 // static
 bool TabAndroid::RegisterTabAndroid(JNIEnv* env) {
   return RegisterNativesImpl(env);
 }