Fix fullscreen elements in pinch viewport mode.

Source/core/rendering/RenderFullScreen.cpp

Index: Source/core/rendering/RenderFullScreen.cpp
diff --git a/Source/core/rendering/RenderFullScreen.cpp b/Source/core/rendering/RenderFullScreen.cpp
index 39f9c11fe6efea69440bd02282a707670912dc61..7cc0ac00bd29fea95a16681bfedc2ac2c5636e98 100644
--- a/Source/core/rendering/RenderFullScreen.cpp
+++ b/Source/core/rendering/RenderFullScreen.cpp
@@ -26,8 +26,12 @@
 #include "core/rendering/RenderFullScreen.h"
 
 #include "core/dom/Fullscreen.h"
+#include "core/page/Chrome.h"
+#include "core/page/Page.h"
 #include "core/rendering/RenderBlockFlow.h"
 
+#include "public/platform/WebScreenInfo.h"
+
 using namespace blink;
 
 class RenderFullScreenPlaceholder FINAL : public RenderBlockFlow {
@@ -88,7 +92,7 @@ void RenderFullScreen::willBeDestroyed()
     RenderFlexibleBox::willBeDestroyed();
 }
 
-static PassRefPtr<RenderStyle> createFullScreenStyle()
+void RenderFullScreen::updateStyle()
 {
     RefPtr<RenderStyle> fullscreenStyle = RenderStyle::createDefaultStyle();
 
@@ -104,14 +108,16 @@ static PassRefPtr<RenderStyle> createFullScreenStyle()
     fullscreenStyle->setFlexDirection(FlowColumn);
 
     fullscreenStyle->setPosition(FixedPosition);
-    fullscreenStyle->setWidth(Length(100.0, Percent));
-    fullscreenStyle->setHeight(Length(100.0, Percent));
     fullscreenStyle->setLeft(Length(0, blink::Fixed));
     fullscreenStyle->setTop(Length(0, blink::Fixed));
 
+    IntSize screenSize = IntRect(document().page()->chrome().screenInfo().rect).size();
+    fullscreenStyle->setWidth(Length(screenSize.width(), blink::Fixed));
+    fullscreenStyle->setHeight(Length(screenSize.height(), blink::Fixed));
+
     fullscreenStyle->setBackgroundColor(StyleColor(Color::black));
 
-    return fullscreenStyle.release();
+    setStyle(fullscreenStyle);
 }
 
 RenderObject* RenderFullScreen::wrapRenderer(RenderObject* object, RenderObject* parent, Document* document)
@@ -121,7 +127,7 @@ RenderObject* RenderFullScreen::wrapRenderer(RenderObject* object, RenderObject*
     DeprecatedDisableModifyRenderTreeStructureAsserts disabler;
 
     RenderFullScreen* fullscreenRenderer = RenderFullScreen::createAnonymous(document);
-    fullscreenRenderer->setStyle(createFullScreenStyle());
+    fullscreenRenderer->updateStyle();
     if (parent && !parent->isChildAllowed(fullscreenRenderer, fullscreenRenderer->style())) {
         fullscreenRenderer->destroy();
         return 0;