Merge remote-tracking branch 'origin/feature/bbEnhancements/27.0.1453.110' into feature/bbEnhancements/28.0.1500.95

Conflicts:
	chromium/src/third_party/WebKit/Source/WebCore/WebCore.gyp/WebCore.gyp
	chromium/src/third_party/WebKit/Source/WebCore/WebCore.gypi
	chromium/src/third_party/WebKit/Source/WebCore/loader/EmptyClients.h
	chromium/src/third_party/WebKit/Source/core/page/DOMWindow.cpp
	chromium/src/third_party/WebKit/Source/core/page/DOMWindow.idl
	chromium/src/third_party/WebKit/Source/core/page/DragController.cpp
Import gyp/gypi changes and also EmptyClients.h change

These changes were not included in the previous merge because git rename
detection did not find the necessary files.
Fix compile errors for v28