<third_party/WebKit> Disable "rubber-banding" on Mac

Rubber-banding is the scrolling effect on Mac when overscrolling
which does not work with Qt and also causes a crash with branch 1750.
Disable the feature for now.

Change-Id: I89f315c2dbb1ed4362b96201566acc784e4bdf96
Reviewed-by: Zeno Albisser <[email protected]>

Author: bbandix

chromium/third_party/WebKit/Source/config.h

@@ -97,7 +97,6 @@
 
 #if OS(MACOSX)
 #define WTF_USE_CF 1
-#define WTF_USE_RUBBER_BANDING 1
 
 /* We can't override the global operator new and delete on OS(MACOSX) because
  * some object are allocated by WebKit and deallocated by the embedder. */