Make tab audible and muted states and cause available for an extension API

content/browser/web_contents/web_contents_impl.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 "content/browser/web_contents/web_contents_impl.h"
 
 #include <utility>
 
 #include "base/command_line.h"
 #include "base/debug/trace_event.h"
@@ skipping 313 matching lines @@
       currentPinchZoomStepDelta_(0),
       render_view_message_source_(NULL),
       fullscreen_widget_routing_id_(MSG_ROUTING_NONE),
       fullscreen_widget_had_focus_at_shutdown_(false),
       is_subframe_(false),
       force_disable_overscroll_content_(false),
       last_dialog_suppressed_(false),
       geolocation_service_context_(new GeolocationServiceContext()),
       accessibility_mode_(
           BrowserAccessibilityStateImpl::GetInstance()->accessibility_mode()),
-      audio_stream_monitor_(this),
+      audio_stream_monitor_(base::Bind(
+          &WebContentsImpl::NotifyAudibleStateChanged, base::Unretained(this))),
       loading_weak_factory_(this) {
   for (size_t i = 0; i < g_created_callbacks.Get().size(); i++)
     g_created_callbacks.Get().at(i).Run(this);
   frame_tree_.SetFrameRemoveListener(
       base::Bind(&WebContentsImpl::OnFrameRemoved,
                  base::Unretained(this)));
 }
 
 WebContentsImpl::~WebContentsImpl() {
   is_being_destroyed_ = true;
@@ skipping 597 matching lines @@
 }
 
 int WebContentsImpl::GetCapturerCount() const {
   return capturer_count_;
 }
 
 bool WebContentsImpl::IsAudioMuted() const {
   return audio_muter_.get() && audio_muter_->is_muting();
 }
 
-void WebContentsImpl::SetAudioMuted(bool mute) {
-  DVLOG(1) << "SetAudioMuted(mute=" << mute << "), was " << IsAudioMuted()
-           << " for WebContentsImpl@" << this;
+void WebContentsImpl::SetAudioMuted(bool muted, const std::string& cause) {
+  DVLOG(1) << "SetAudioMuted(muted=" << muted << ", cause =" << cause
+           << "), was " << IsAudioMuted() << " for WebContentsImpl@" << this;
 
-  if (mute == IsAudioMuted())
+  if (muted == IsAudioMuted())
     return;
 
-  if (mute) {
+  NotifyMutedStateChanged(muted, cause);
+
+  if (muted) {
     if (!audio_muter_)
       audio_muter_.reset(new WebContentsAudioMuter(this));
     audio_muter_->StartMuting();
   } else {
     DCHECK(audio_muter_);
     audio_muter_->StopMuting();
   }
 
   // Notification for UI updates in response to the changed muting state.
   NotifyNavigationStateChanged(INVALIDATE_TYPE_TAB);
@@ skipping 18 matching lines @@
 base::TerminationStatus WebContentsImpl::GetCrashedStatus() const {
   return crashed_status_;
 }
 
 bool WebContentsImpl::IsBeingDestroyed() const {
   return is_being_destroyed_;
 }
 
 void WebContentsImpl::NotifyNavigationStateChanged(
     InvalidateTypes changed_flags) {
-  // Create and release the audio power save blocker depending on whether the
-  // tab is actively producing audio or not.
-  if (changed_flags == INVALIDATE_TYPE_TAB &&
-      AudioStreamMonitor::monitoring_available()) {
-    if (WasRecentlyAudible()) {
-      if (!audio_power_save_blocker_)
-        CreateAudioPowerSaveBlocker();
-    } else {
-      audio_power_save_blocker_.reset();
-    }
-  }
-
   if (delegate_)
     delegate_->NavigationStateChanged(this, changed_flags);
 }
 
+void WebContentsImpl::NotifyAudibleStateChanged(bool is_audible) {
+  DCHECK(AudioStreamMonitor::monitoring_available());
+
+  // Create and release the audio power save blocker depending on whether the
+  // tab is actively producing audio or not.
+  if (WasRecentlyAudible()) {
+    if (!audio_power_save_blocker_)
+      CreateAudioPowerSaveBlocker();
+  } else {
+    audio_power_save_blocker_.reset();
+  }
+
+  // Notify delegate that a UI update may be needed for new tab media state.
+  NotifyNavigationStateChanged(INVALIDATE_TYPE_TAB);
+
+  FOR_EACH_OBSERVER(WebContentsObserver, observers_, TabAudible(is_audible));
+}
+
+void WebContentsImpl::NotifyMutedStateChanged(
+    bool is_muted,
+    const std::string& cause) {
+  FOR_EACH_OBSERVER(WebContentsObserver, observers_, TabMuted(is_muted, cause));
+}
+
 base::TimeTicks WebContentsImpl::GetLastActiveTime() const {
   return last_active_time_;
 }
 
 void WebContentsImpl::WasShown() {
   controller_.SetActive(true);
 
   std::set<RenderWidgetHostView*> widgets = GetRenderWidgetHostViewsInTree();
   for (std::set<RenderWidgetHostView*>::iterator iter = widgets.begin();
        iter != widgets.end();
@@ skipping 3324 matching lines @@
   node->render_manager()->ResumeResponseDeferredAtStart();
 }
 
 void WebContentsImpl::SetForceDisableOverscrollContent(bool force_disable) {
   force_disable_overscroll_content_ = force_disable;
   if (view_)
     view_->SetOverscrollControllerEnabled(CanOverscrollContent());
 }
 
 }  // namespace content