Make StyleRareNonInheritedData::draggable_regions a bit field.

third_party/WebKit/Source/core/style/ComputedStyle.h

Index: third_party/WebKit/Source/core/style/ComputedStyle.h
diff --git a/third_party/WebKit/Source/core/style/ComputedStyle.h b/third_party/WebKit/Source/core/style/ComputedStyle.h
index 2bf27aa48daceb6dd597a342271789111a0d699c..1771f1881ea48557ad9392eb90c7a460117200d4 100644
--- a/third_party/WebKit/Source/core/style/ComputedStyle.h
+++ b/third_party/WebKit/Source/core/style/ComputedStyle.h
@@ -1528,10 +1528,12 @@ class CORE_EXPORT ComputedStyle : public ComputedStyleBase<ComputedStyle>,
 
   // -webkit-app-region
   DraggableRegionMode GetDraggableRegionMode() const {
-    return rare_non_inherited_data_->draggable_region_mode_;
+    return static_cast<DraggableRegionMode>(
+        rare_non_inherited_data_->draggable_region_mode_);
   }
   void SetDraggableRegionMode(DraggableRegionMode v) {
-    SET_VAR(rare_non_inherited_data_, draggable_region_mode_, v);
+    SET_VAR(rare_non_inherited_data_, draggable_region_mode_,
+            static_cast<unsigned>(v));
   }
 
   // -webkit-appearance