Implement "Look Up In Dictionary" context menu item asynchronously. (OS X)

content/browser/renderer_host/text_input_client_mac.h

Index: content/browser/renderer_host/text_input_client_mac.h
diff --git a/content/browser/renderer_host/text_input_client_mac.h b/content/browser/renderer_host/text_input_client_mac.h
index 4e50eff5c7e39c0fc8e9227154c945ba16aa5bce..e82611f2eb95e41883a200e2eadfe60928a19a9a 100644
--- a/content/browser/renderer_host/text_input_client_mac.h
+++ b/content/browser/renderer_host/text_input_client_mac.h
@@ -81,6 +81,19 @@ class CONTENT_EXPORT TextInputClientMac {
   // GetStringAtPoint.
   void GetStringAtPointReply(NSAttributedString*, NSPoint);
 
+  // This async method is invoked from RenderWidgetHostViewMacDictionaryHelper's
+  // ShowDefinitionForSelection().
+  // The reply callback will be invoked from the IO thread, the caller is
+  // responsible for bouncing to the main thread if necessary.
+  // The callback parameters provide the attributed word under the point and
+  // the lower left baseline point of the text.
+  void GetStringFromRange(RenderWidgetHost* rwh,
+                          NSRange range,
+                          void (^replyHandler)(NSAttributedString*, NSPoint));
+  // This is called on the IO thread when we get the renderer's reply for
+  // GetStringFromRange.
+  void GetStringFromRangeReply(NSAttributedString*, NSPoint);
+
  private:
   friend struct DefaultSingletonTraits<TextInputClientMac>;
   TextInputClientMac();
@@ -102,7 +115,10 @@ class CONTENT_EXPORT TextInputClientMac {
   base::Lock lock_;
   base::ConditionVariable condition_;
 
-  base::mac::ScopedBlock<void(^)(NSAttributedString*, NSPoint)> replyHandler_;
+  base::mac::ScopedBlock<void(^)(NSAttributedString*, NSPoint)>
+      replyForPointHandler_;
+  base::mac::ScopedBlock<void(^)(NSAttributedString*, NSPoint)>
+      replyForRangeHandler_;
 
   DISALLOW_COPY_AND_ASSIGN(TextInputClientMac);
 };