Improve the fixed element position calculation

In the previous WAR, we get the screen size from UI thread at every draw call.
That is awkward.

Now with Java side fix, we can get the screen size from setSize call now.
However, forcing a full re-layout seems like an expensive operation.
What we need to make the webkit to know the update can be done by just
updating the fixed position elements only.

So I have done these:
1. Take away the WAR by forcing the update at the convertToLayerCoord.
2. Get rid of the UI thread stuff used to tell WebViewCore the screen size.
And get rid of the redundant variables, too.
3. update the fixed element at the setSize time.

BTW, I also rename the PlatformBridge functions name.

bug: 3397602

Change-Id: I0c422ecdb570de89aecb6e568d5067acf18ecfc6

1 files changed, 2 insertions, 2 deletions

diff --git a/WebCore/rendering/RenderBox.cpp b/WebCore/rendering/RenderBox.cpp
index 3c8e2ca..ebd7d54 100644
--- a/WebCore/rendering/RenderBox.cpp
+++ b/WebCore/rendering/RenderBox.cpp
@@ -2085,7 +2085,7 @@ int RenderBox::containingBlockWidthForPositioned(const RenderBoxModelObject* con
     // That is in the doc coordindate.
     if (style()->position() == FixedPosition && containingBlock->isRenderView()) {
         const RenderView* view = toRenderView(containingBlock);
-        return PlatformBridge::visibleScreenWidth(view->frameView());
+        return PlatformBridge::screenWidthInDocCoord(view->frameView());
     }
 #endif
     if (containingBlock->isBox()) {
@@ -2123,7 +2123,7 @@ int RenderBox::containingBlockHeightForPositioned(const RenderBoxModelObject* co
     // That is in the doc coordindate.
     if (style()->position() == FixedPosition && containingBlock->isRenderView()) {
         const RenderView* view = toRenderView(containingBlock);
-        return PlatformBridge::visibleScreenHeight(view->frameView());
+        return PlatformBridge::screenHeightInDocCoord(view->frameView());
     }
 #endif
     int heightResult = 0;