[Display Cutout] Add feature for media controls

Add a feature for media controls to recognise a gesture
and expand into the display cutout.

BUG=849790

Change-Id: Ice6de82f4fb94e366fca68338a55236fa1f05c8a
Reviewed-on: https://chromium-review.googlesource.com/1087710Reviewed-by: Jochen Eisinger <jochen@chromium.org>
Commit-Queue: Becca Hughes <beccahughes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#568142}

chrome/browser/about_flags.cc

@@ -3932,6 +3932,13 @@ const FeatureEntry kFeatureEntries[] = {
      flag_descriptions::kEnableBlinkHeapIncrementalMarkingDescription, kOsAll,
      FEATURE_VALUE_TYPE(features::kBlinkHeapIncrementalMarking)},
 
+#if defined(OS_ANDROID)
+    {"enable-media-controls-expand-gesture",
+     flag_descriptions::kEnableMediaControlsExpandGestureName,
+     flag_descriptions::kEnableMediaControlsExpandGestureDescription,
+     kOsAndroid, FEATURE_VALUE_TYPE(media::kMediaControlsExpandGesture)},
+#endif
+
     // NOTE: Adding a new flag requires adding a corresponding entry to enum
     // "LoginCustomFlags" in tools/metrics/histograms/enums.xml. See "Flag
     // Histograms" in tools/metrics/histograms/README.md (run the

chrome/browser/flag_descriptions.cc

@@ -2146,6 +2146,12 @@ const char kEnableDataReductionProxyMainMenuName[] =
 const char kEnableDataReductionProxyMainMenuDescription[] =
     "Enables the Data Saver menu item in the main menu";
 
+const char kEnableMediaControlsExpandGestureName[] =
+    "Enable Media Controls Expand Gesture";
+const char kEnableMediaControlsExpandGestureDescription[] =
+    "Enables a gesture to be used on the media controls to extend the video "
+    "into the Display Cutout area.";
+
 const char kEnableOmniboxClipboardProviderName[] =
     "Omnibox clipboard URL suggestions";
 const char kEnableOmniboxClipboardProviderDescription[] =

chrome/browser/flag_descriptions.h

@@ -1308,6 +1308,9 @@ extern const char kEnableCustomFeedbackUiDescription[];
 extern const char kEnableDataReductionProxyMainMenuName[];
 extern const char kEnableDataReductionProxyMainMenuDescription[];
 
+extern const char kEnableMediaControlsExpandGestureName[];
+extern const char kEnableMediaControlsExpandGestureDescription[];
+
 extern const char kEnableOmniboxClipboardProviderName[];
 extern const char kEnableOmniboxClipboardProviderDescription[];
 

media/base/media_switches.cc

@@ -333,6 +333,10 @@ const base::Feature kAutoplayIgnoreWebAudio{"AutoplayIgnoreWebAudio",
                                             base::FEATURE_ENABLED_BY_DEFAULT};
 
 #if defined(OS_ANDROID)
+// Enable a gesture to make the media controls expaned into the display cutout.
+const base::Feature kMediaControlsExpandGesture{
+    "MediaControlsExpandGesture", base::FEATURE_DISABLED_BY_DEFAULT};
+
 // Lock the screen orientation when a video goes fullscreen.
 const base::Feature kVideoFullscreenOrientationLock{
     "VideoFullscreenOrientationLock", base::FEATURE_ENABLED_BY_DEFAULT};

media/base/media_switches.h

@@ -137,6 +137,7 @@ MEDIA_EXPORT extern const base::Feature kUseSurfaceLayerForVideo;
 MEDIA_EXPORT extern const base::Feature kUseModernMediaControls;
 
 #if defined(OS_ANDROID)
+MEDIA_EXPORT extern const base::Feature kMediaControlsExpandGesture;
 MEDIA_EXPORT extern const base::Feature kVideoFullscreenOrientationLock;
 MEDIA_EXPORT extern const base::Feature kVideoRotateToFullscreen;
 MEDIA_EXPORT extern const base::Feature kMediaDrmPersistentLicense;

third_party/blink/public/platform/web_runtime_features.h

@@ -196,6 +196,7 @@ class WebRuntimeFeatures {
   BLINK_PLATFORM_EXPORT static void EnableExperimentalProductivityFeatures(
       bool);
   BLINK_PLATFORM_EXPORT static void EnableAutoplayIgnoresWebAudio(bool);
+  BLINK_PLATFORM_EXPORT static void EnableMediaControlsExpandGesture(bool);
 
  private:
   WebRuntimeFeatures();

third_party/blink/renderer/platform/exported/web_runtime_features.cc

@@ -540,4 +540,8 @@ void WebRuntimeFeatures::EnableAutoplayIgnoresWebAudio(bool enable) {
   RuntimeEnabledFeatures::SetAutoplayIgnoresWebAudioEnabled(enable);
 }
 
+void WebRuntimeFeatures::EnableMediaControlsExpandGesture(bool enable) {
+  RuntimeEnabledFeatures::SetMediaControlsExpandGestureEnabled(enable);
+}
+
 }  // namespace blink

tools/metrics/histograms/enums.xml

@@ -27315,6 +27315,7 @@ from previous Chrome versions.
   <int value="-1136509631" label="ssl-interstitial-v1"/>
   <int value="-1134307340" label="stop-loading-in-background:enabled"/>
   <int value="-1132704128" label="AndroidPaymentAppsFilter:disabled"/>
+  <int value="-1128912963" label="MediaControlsExpandGesture:disabled"/>
   <int value="-1127996427" label="enable-files-details-panel"/>
   <int value="-1126217973" label="IdleTimeSpellChecking:disabled"/>
   <int value="-1125840399" label="ViewsBrowserWindows:enabled"/>
@@ -28006,6 +28007,7 @@ from previous Chrome versions.
   <int value="468959230"
       label="enable-non-validating-reload-on-refresh-content"/>
   <int value="470011024" label="NonValidatingReloadOnNormalReload:enabled"/>
+  <int value="471969274" label="MediaControlsExpandGesture:enabled"/>
   <int value="474743272" label="material-design-ink-drop"/>
   <int value="475858648"
       label="OverlayScrollbarFlashAfterAnyScrollUpdate:disabled"/>