Allow style sharing for canvas, iframe, embed and object.

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

Index: third_party/WebKit/Source/core/dom/Element.cpp
diff --git a/third_party/WebKit/Source/core/dom/Element.cpp b/third_party/WebKit/Source/core/dom/Element.cpp
index c9ea807bae982ef00154a3280aaaee7081d32fcc..93ac883057d67cf9520f0d41b323434e5fed3312 100644
--- a/third_party/WebKit/Source/core/dom/Element.cpp
+++ b/third_party/WebKit/Source/core/dom/Element.cpp
@@ -3550,11 +3550,6 @@ bool Element::supportsStyleSharing() const
         return false;
     if (hasAnimations())
         return false;
-    // Turn off style sharing for elements that can gain layers for reasons outside of the style system.
-    // See comments in LayoutObject::setStyle().
-    // FIXME: Why does gaining a layer from outside the style system require disabling sharing?
-    if (isHTMLFrameElementBase(*this) || isHTMLPlugInElement(*this) || isHTMLCanvasElement(*this))
-        return false;
     if (Fullscreen::isActiveFullScreenElement(*this))
         return false;
     return true;