Fixed Android text selection by redefining |button| value.

third_party/WebKit/public/platform/WebPointerProperties.h

Index: third_party/WebKit/public/platform/WebPointerProperties.h
diff --git a/third_party/WebKit/public/platform/WebPointerProperties.h b/third_party/WebKit/public/platform/WebPointerProperties.h
index 49a142e785cafeab892aff39b4c180a9edd36d40..ad2704ae526e8ecf5eb670d1aa0ef4e7cabbd00d 100644
--- a/third_party/WebKit/public/platform/WebPointerProperties.h
+++ b/third_party/WebKit/public/platform/WebPointerProperties.h
@@ -80,7 +80,13 @@ class WebPointerProperties {
   // degrees in the range [0,359]. Always 0 if the device does not support it.
   int twist;
 
+  // - For pointerup/down events, the button of pointing device that triggered
+  // the event.
+  // - For other events, the button that was depressed during the move event. If
+  // multiple buttons were depressed, one of the depressed buttons (platform
+  // dependent).
   Button button;
+
   PointerType pointerType;
 
   int movementX;