When we get a IME_CANCEL_COMPOSITION event on OSX, clear the

chrome/browser/renderer_host/render_widget_host_view_mac.mm

Index: chrome/browser/renderer_host/render_widget_host_view_mac.mm
diff --git a/chrome/browser/renderer_host/render_widget_host_view_mac.mm b/chrome/browser/renderer_host/render_widget_host_view_mac.mm
index ac130c909343d686a2610917e677cf2203950175..effaf1ed28cd8753ccbeb2c00b9e0d8b8c87b7ac 100644
--- a/chrome/browser/renderer_host/render_widget_host_view_mac.mm
+++ b/chrome/browser/renderer_host/render_widget_host_view_mac.mm
@@ -317,8 +317,10 @@ void RenderWidgetHostViewMac::SetIsLoading(bool is_loading) {
 void RenderWidgetHostViewMac::IMEUpdateStatus(int control,
                                               const gfx::Rect& caret_rect) {
   // Reset the IME state and finish an ongoing composition in the renderer.
-  if (control == IME_DISABLE || control == IME_COMPLETE_COMPOSITION)
+  if (control == IME_DISABLE || control == IME_COMPLETE_COMPOSITION ||
+      control == IME_CANCEL_COMPOSITION) {
     [cocoa_view_ cancelComposition];
+  }
 
   // We need to convert the coordinate of the cursor rectangle sent from the
   // renderer and save it. Our IME backend uses a coordinate system whose