[Blink>Fullscreen] Add UseCounter for fullscreen on orientation change

third_party/WebKit/Source/core/dom/Fullscreen.cpp

Index: third_party/WebKit/Source/core/dom/Fullscreen.cpp
diff --git a/third_party/WebKit/Source/core/dom/Fullscreen.cpp b/third_party/WebKit/Source/core/dom/Fullscreen.cpp
index ff1331bd4cadc423dc311e1626746ce7ce733867..2e9a98908e780fd3be35a8316b4e0f78e1905bb2 100644
--- a/third_party/WebKit/Source/core/dom/Fullscreen.cpp
+++ b/third_party/WebKit/Source/core/dom/Fullscreen.cpp
@@ -87,8 +87,10 @@ bool allowedToRequestFullscreen(Document& document) {
     return true;
 
   //  The algorithm is triggered by a user generated orientation change.
-  if (ScopedOrientationChangeIndicator::processingOrientationChange())
+  if (ScopedOrientationChangeIndicator::processingOrientationChange()) {
+    UseCounter::count(document(), UseCounter::FullscreenOnOrientationChange);

[foolip, 2016/12/07 08:58:32]

Does this actually compile? Should be just document.

[foolip, 2016/12/07 08:58:32]

Suggest FullscreenAllowedByOrientationChange, since there could still be other
things that make it go wrong.

[Zhiqiang Zhang (Slow), 2016/12/07 11:49:58]

Done.

[Zhiqiang Zhang (Slow), 2016/12/07 11:49:58]

Done.

     return true;
+  }
 
   String message = ExceptionMessages::failedToExecute(
       "requestFullscreen", "Element",