Update visual viewport API to take browser zoom into account.

third_party/WebKit/Source/core/frame/VisualViewport.cpp

Index: third_party/WebKit/Source/core/frame/VisualViewport.cpp
diff --git a/third_party/WebKit/Source/core/frame/VisualViewport.cpp b/third_party/WebKit/Source/core/frame/VisualViewport.cpp
index 972c3bd1f4798080d8e9668818e0a3fc4dbaf597..e77b571758d9e313af6e0597453590169c5d483a 100644
--- a/third_party/WebKit/Source/core/frame/VisualViewport.cpp
+++ b/third_party/WebKit/Source/core/frame/VisualViewport.cpp
@@ -211,44 +211,62 @@ void VisualViewport::setScale(float scale)
 
 double VisualViewport::scrollLeft()
 {
+    if (!mainFrame())
+        return 0;
+
     updateLayoutIgnorePendingStylesheets();
 
-    return visibleRect().x();
+    return adjustScrollForAbsoluteZoom(visibleRect().x(), mainFrame()->pageZoomFactor());

[bokan, 2016/04/21 13:03:32]

ComputedStyle.h is a strange place for this function to live. Please move this
function into a new core/page/scrolling/ScrollUtils.h file (this seems like
overkill but we're overdue, other stuff belongs there too).

At the same time, the overload in ComputedStyle that takes (double, const
ComputedStyle&) is unused so remove it. Also rename to
adjustScrollForZoomFactor.

[ymalik, 2016/04/24 02:25:30]

I'll make those changes in a follow up CL if you don't mind. Don't want to
clutter this bug fix with cleanup as the functions are used from a bunch of
places.

 }
 
 double VisualViewport::scrollTop()
 {
+    if (!mainFrame())
+        return 0;
+
     updateLayoutIgnorePendingStylesheets();
 
-    return visibleRect().y();
+    return adjustScrollForAbsoluteZoom(visibleRect().y(), mainFrame()->pageZoomFactor());
 }
 
 void VisualViewport::setScrollLeft(double x)
 {
+    if (!mainFrame())
+        return;
+
     updateLayoutIgnorePendingStylesheets();
 
-    setLocation(FloatPoint(x, visibleRect().y()));
+    setLocation(FloatPoint(x * mainFrame()->pageZoomFactor(), visibleRect().y()));

[bokan, 2016/04/21 13:03:32]

use location().y() rather than visibleRect.

[ymalik, 2016/04/24 02:25:30]

Done.

 }
 
 void VisualViewport::setScrollTop(double y)
 {
+    if (!mainFrame())
+        return;
+
     updateLayoutIgnorePendingStylesheets();
 
-    setLocation(FloatPoint(visibleRect().x(), y));
+    setLocation(FloatPoint(visibleRect().x(), y * mainFrame()->pageZoomFactor()));
 }
 
 double VisualViewport::clientWidth()
 {
+    if (!mainFrame())
+        return 0;
+
     updateLayoutIgnorePendingStylesheets();
 
-    return visibleRect().width();
+    return adjustScrollForAbsoluteZoom(visibleRect().width(), mainFrame()->pageZoomFactor());

[bokan, 2016/04/21 13:03:32]

visibleSize().width() rather than visibleRect

[ymalik, 2016/04/24 02:25:30]

Done.

 }
 
 double VisualViewport::clientHeight()
 {
+    if (!mainFrame())
+        return 0;
+
     updateLayoutIgnorePendingStylesheets();
 
-    return visibleRect().height();
+    return adjustScrollForAbsoluteZoom(visibleRect().height(), mainFrame()->pageZoomFactor());
 }
 
 double VisualViewport::pageScale()