Only show mute icon on tab when sound is playing

This CL adds a check to WasRecentlyAudible before adding a mute icon to
a tab to avoid always showing a mute icon when a tab is muted. This also
adds the fade animation to the (mute icon)->(no icon) transition. Since
adding the fade animation breaks a TabTest unit test (which worked under
the assumption that each of its transitions was instantaneous), this CL
also manually stops fade animations in that test.

Bug: 785406
Change-Id: I0d7fd732b605f634f9df59b736dd7f19c382a09e
Reviewed-on: https://chromium-review.googlesource.com/889178Reviewed-by: Yuri Wiitala <miu@chromium.org>
Commit-Queue: Tommy Steimel <steimel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#532652}

chrome/browser/ui/tabs/tab_utils.cc

@@ -170,10 +170,11 @@ TabAlertState GetTabAlertStateForContents(content::WebContents* contents) {
   if (usb_tab_helper && usb_tab_helper->IsDeviceConnected())
     return TabAlertState::USB_CONNECTED;
 
-  if (contents->IsAudioMuted())
-    return TabAlertState::AUDIO_MUTING;
-  if (contents->WasRecentlyAudible())
+  if (contents->WasRecentlyAudible()) {
+    if (contents->IsAudioMuted())
+      return TabAlertState::AUDIO_MUTING;
     return TabAlertState::AUDIO_PLAYING;
+  }
 
   return TabAlertState::NONE;
 }

chrome/browser/ui/views/tabs/alert_indicator_button.cc

@@ -93,9 +93,7 @@ void AlertIndicatorButton::TransitionToAlertState(TabAlertState next_state) {
   if ((alert_state_ == TabAlertState::AUDIO_PLAYING &&
        next_state == TabAlertState::AUDIO_MUTING) ||
       (alert_state_ == TabAlertState::AUDIO_MUTING &&
-       next_state == TabAlertState::AUDIO_PLAYING) ||
-      (alert_state_ == TabAlertState::AUDIO_MUTING &&
-       next_state == TabAlertState::NONE)) {
+       next_state == TabAlertState::AUDIO_PLAYING)) {
     // Instant user feedback: No fade animation.
     showing_alert_state_ = next_state;
     fade_animation_.reset();

chrome/browser/ui/views/tabs/alert_indicator_button.h

@@ -85,6 +85,7 @@ class AlertIndicatorButton : public views::ImageButton,
 
  private:
   friend class AlertIndicatorButtonTest;
+  friend class TabTest;
   class FadeAnimationDelegate;
 
   // Returns the tab (parent view) of this AlertIndicatorButton.

chrome/browser/ui/views/tabs/tab_unittest.cc

@@ -233,6 +233,15 @@ class TabTest : public views::ViewsTestBase {
     }
   }
 
+  static void StopFadeAnimationIfNecessary(const Tab& tab) {
+    // Stop the fade animation directly instead of waiting an unknown number of
+    // seconds.
+    if (gfx::Animation* fade_animation =
+            tab.alert_indicator_button_->fade_animation_.get()) {
+      fade_animation->Stop();
+    }
+  }
+
  protected:
   void InitWidget(Widget* widget) {
     Widget::InitParams params(CreateParams(Widget::InitParams::TYPE_WINDOW));
@@ -314,6 +323,7 @@ TEST_F(TabTest, LayoutAndVisibilityOfElements) {
         controller.set_active_tab(is_active_tab);
         data.alert_state = alert_state;
         tab.SetData(data);
+        StopFadeAnimationIfNecessary(tab);
 
         // Test layout for every width from standard to minimum.
         gfx::Rect bounds(gfx::Point(0, 0), Tab::GetStandardSize());