Implement "Look Up In Dictionary" context menu item asynchronously.

content/browser/renderer_host/render_widget_host_view_mac_dictionary_helper.mm

Index: content/browser/renderer_host/render_widget_host_view_mac_dictionary_helper.mm
diff --git a/content/browser/renderer_host/render_widget_host_view_mac_dictionary_helper.mm b/content/browser/renderer_host/render_widget_host_view_mac_dictionary_helper.mm
index 92f10bc2688d6d9e84c2a68b9bc772205fc97c83..69e99227575ed403a9c13973cc0aef403c290f7c 100644
--- a/content/browser/renderer_host/render_widget_host_view_mac_dictionary_helper.mm
+++ b/content/browser/renderer_host/render_widget_host_view_mac_dictionary_helper.mm
@@ -22,38 +22,12 @@ void RenderWidgetHostViewMacDictionaryHelper::SetTargetView(
 
 void RenderWidgetHostViewMacDictionaryHelper::ShowDefinitionForSelection() {
   NSRange selection_range = [view_->cocoa_view() selectedRange];
-  NSAttributedString* attr_string =
-      [view_->cocoa_view() attributedSubstringForProposedRange:selection_range
-                                                   actualRange:nil];
-  if (!attr_string) {
-    if (view_->selected_text().empty())
-      return;
-    // The PDF plugin does not support getting the attributed string. Until it
-    // does, use NSPerformService(), which opens Dictionary.app.
-    // http://crbug.com/152438
-    // TODO(asvitkine): This should be removed after the above support is added.
-    NSString* text = base::SysUTF8ToNSString(view_->selected_text());
-    NSPasteboard* pasteboard = [NSPasteboard pasteboardWithUniqueName];
-    NSArray* types = [NSArray arrayWithObject:NSStringPboardType];
-    [pasteboard declareTypes:types owner:nil];
-    if ([pasteboard setString:text forType:NSStringPboardType])
-      NSPerformService(@"Look Up in Dictionary", pasteboard);
-    return;
-  }
-
   NSRect rect =
       [view_->cocoa_view() firstViewRectForCharacterRange:selection_range
                                               actualRange:nil];
-
-  NSDictionary* attrs = [attr_string attributesAtIndex:0 effectiveRange:nil];
-  NSFont* font = [attrs objectForKey:NSFontAttributeName];
-  rect.origin.y += NSHeight(rect) - [font ascender];
-
   rect.origin.x += offset_.x();
-  rect.origin.y += offset_.y();
-
-  [target_view_->cocoa_view() showDefinitionForAttributedString:attr_string
-                                                        atPoint:rect.origin];
+  rect.origin.y += NSHeight(rect) + offset_.y();
+  [view_->cocoa_view() showLookUpDictionaryOverlayAtPoint:rect.origin];
 }
 
 }  // namespace content