Revert of Remove enable/disable wheel gestures setting.

content/browser/renderer_host/overscroll_controller.cc

Index: content/browser/renderer_host/overscroll_controller.cc
diff --git a/content/browser/renderer_host/overscroll_controller.cc b/content/browser/renderer_host/overscroll_controller.cc
index 2f0630274351221f28e65152440792e188064304..34c631a56ddb2663c61b090204d8c784a6b37eb5 100644
--- a/content/browser/renderer_host/overscroll_controller.cc
+++ b/content/browser/renderer_host/overscroll_controller.cc
@@ -7,6 +7,7 @@
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "content/browser/renderer_host/overscroll_controller_delegate.h"
+#include "content/common/input/input_event_utils.h"
 #include "content/public/browser/overscroll_configuration.h"
 #include "content/public/common/content_switches.h"
 
@@ -35,13 +36,15 @@
       scroll_state_(STATE_UNKNOWN),
       overscroll_delta_x_(0.f),
       overscroll_delta_y_(0.f),
-      delegate_(NULL) {}
+      delegate_(NULL),
+      use_gesture_wheel_scrolling_(UseGestureBasedWheelScrolling()) {}
 
 OverscrollController::~OverscrollController() {
 }
 
 bool OverscrollController::ShouldProcessEvent(
     const blink::WebInputEvent& event) {
+  if (use_gesture_wheel_scrolling_) {
     switch (event.type) {
       case blink::WebInputEvent::MouseWheel:
         return false;
@@ -73,6 +76,7 @@
       default:
         break;
     }
+  }
   return true;
 }