Move willEnterFullscreen to WebRemoteFrame.

third_party/WebKit/Source/web/WebRemoteFrameImpl.cpp

Index: third_party/WebKit/Source/web/WebRemoteFrameImpl.cpp
diff --git a/third_party/WebKit/Source/web/WebRemoteFrameImpl.cpp b/third_party/WebKit/Source/web/WebRemoteFrameImpl.cpp
index 30c95b233a444927b9859f349f167a448c149c11..48bb0c80faad006c0495a2f49e6b3908664b7a54 100644
--- a/third_party/WebKit/Source/web/WebRemoteFrameImpl.cpp
+++ b/third_party/WebKit/Source/web/WebRemoteFrameImpl.cpp
@@ -4,6 +4,7 @@
 
 #include "web/WebRemoteFrameImpl.h"
 
+#include "core/dom/Fullscreen.h"
 #include "core/dom/RemoteSecurityContext.h"
 #include "core/dom/SecurityContext.h"
 #include "core/frame/FrameView.h"
@@ -706,6 +707,29 @@ bool WebRemoteFrameImpl::isIgnoredForHitTest() const
     return owner->layoutObject()->style()->pointerEvents() == PE_NONE;
 }
 
+void WebRemoteFrameImpl::willEnterFullScreen()
+{
+    // This should only ever be called when the FrameOwner is local.
+    HTMLFrameOwnerElement* ownerElement = toHTMLFrameOwnerElement(frame()->owner());
+
+    // Call requestFullscreen() on |ownerElement| to make it the provisional
+    // fullscreen element in FullscreenController, and to prepare
+    // fullscreenchange events that will need to fire on it and its (local)
+    // ancestors. The events will be triggered if/when fullscreen is entered.
+    //
+    // Passing |forCrossProcessAncestor| to requestFullscreen is necessary
+    // because:
+    // - |ownerElement| will need :-webkit-full-screen-ancestor style in
+    //   addition to :-webkit-full-screen.
+    // - there's no need to resend the ToggleFullscreen IPC to the browser
+    //   process.
+    //
+    // TODO(alexmos): currently, this assumes prefixed requests, but in the
+    // future, this should plumb in information about which request type
+    // (prefixed or unprefixed) to use for firing fullscreen events.
+    Fullscreen::from(ownerElement->document()).requestFullscreen(*ownerElement, Fullscreen::PrefixedRequest, true /* forCrossProcessAncestor */);
+}
+
 WebRemoteFrameImpl::WebRemoteFrameImpl(WebTreeScopeType scope, WebRemoteFrameClient* client)
     : WebRemoteFrame(scope)
     , m_frameClient(RemoteFrameClientImpl::create(this))