WIP - WebMediaPlayer switch media renderer.

third_party/WebKit/Source/web/FullscreenController.cpp

Index: third_party/WebKit/Source/web/FullscreenController.cpp
diff --git a/third_party/WebKit/Source/web/FullscreenController.cpp b/third_party/WebKit/Source/web/FullscreenController.cpp
index 1d0f0fcc1cfe818faf7921877ab15ccf4eba3ca6..ee1303bebd4256fed53f0ae8c8c1eb773633eccc 100644
--- a/third_party/WebKit/Source/web/FullscreenController.cpp
+++ b/third_party/WebKit/Source/web/FullscreenController.cpp
@@ -37,9 +37,11 @@
 #include "core/frame/PageScaleConstraintsSet.h"
 #include "core/html/HTMLMediaElement.h"
 #include "core/html/HTMLVideoElement.h"
+#include "platform/LayoutTestSupport.h"
 #include "platform/RuntimeEnabledFeatures.h"
 #include "public/platform/WebLayerTreeView.h"
 #include "public/web/WebFrameClient.h"
+#include "third_party/WebKit/Source/core/dom/TagCollection.h"
 #include "web/WebLocalFrameImpl.h"
 #include "web/WebSettingsImpl.h"
 #include "web/WebViewImpl.h"
@@ -84,6 +86,21 @@ void FullscreenController::didEnterFullscreen()
     Fullscreen::from(document).didEnterFullscreenForElement(element);
     DCHECK_EQ(Fullscreen::currentFullScreenElementFrom(document), element);
 
+    // Notify WebMediaPlayer when video enters full screen, and the full screen
+    // element is not a HTMLMediaElement.
+    if (!isHTMLMediaElement(element)) {

[liberato (no reviews please), 2016/08/03 21:54:17]

could early-out on isRunningLayoutTest here, rather than in the loop.

actually, there's a bunch of code that's identical between the enter / exit
cases.  maybe some helper:

HTMLMediaElement* FullscreenController::findChildMediaElement(element)

also, what is the desired behavior if
 - more than one media element exists under |element|?
 - a media element is not visible in the sense of css display:none?

[xjz, 2016/08/04 02:28:15]

Done with the helper. 
Yes, it could have multiple media elements under this |element| or/and invisible
elements. The desired behavior here is to notify each media element that its
parent goes to fullscreen. 

+        TagCollection* collection = element->getElementsByTagName("video");
+        for (unsigned i = 0; i < collection->length(); ++i) {
+            Element* collectElement = collection->item(i);
+            if (isHTMLMediaElement(collectElement)) {

[liberato (no reviews please), 2016/08/03 21:54:17]

if (!is)... continue; will save {} nesting.

[xjz, 2016/08/04 02:28:15]

Done. 

+                HTMLMediaElement* videoElement = toHTMLMediaElement(collectElement);
+                if (videoElement->webMediaPlayer()
+                    && !LayoutTestSupport::isRunningLayoutTest())
+                    videoElement->webMediaPlayer()->enteredFullscreen();

[liberato (no reviews please), 2016/08/03 21:54:17]

entered/exitedFullscreen shouldn't be called for an ancestor case. it will
trigger an optimization on android that will break standards conformance,
unfortunately.  my current project is to fix that.

i recommend adding something like ancestorEntered/ExitedFullscreen() to
WebMediaPlayer.  whatever processing fullscreen does for cast will have to
happen in both the ancestor and self cases, but most of the existing non-cast
logic will happen only in the self case.

[xjz, 2016/08/04 02:28:16]

I agree. Now add WebMediaPlayer::updateMediaInFullscreen() for this purpose, and
keep the original non-cast logic. 

+            }
+        }
+    }
+
     if (isHTMLVideoElement(element)) {
         HTMLVideoElement* videoElement = toHTMLVideoElement(element);
         if (videoElement->usesOverlayFullscreenVideo() && m_webViewImpl->layerTreeView())
@@ -119,6 +136,20 @@ void FullscreenController::didExitFullscreen()
                 if (m_haveEnteredFullscreen)
                     m_needsScrollAndScaleRestore = true;
 
+                // Notify WebMediaPlayer when video exits full screen, and the
+                // full screen element is not a HTMLMediaElement.
+                if (!isHTMLMediaElement(element)) {
+                    TagCollection* collection = element->getElementsByTagName("video");
+                    for (unsigned i = 0; i < collection->length(); ++i) {
+                        Element* collectElement = collection->item(i);
+                        if (isHTMLMediaElement(collectElement)) {
+                            HTMLMediaElement* videoElement = toHTMLMediaElement(collectElement);
+                            if (videoElement->webMediaPlayer())
+                                videoElement->webMediaPlayer()->exitedFullscreen();
+                        }
+                    }
+                }
+
                 fullscreen->didExitFullscreen();
             }
         }