[Mac]: Enable speech sub-menu under the edit menu and pipe it through to the renderer.

content/browser/renderer_host/render_widget_host_view_mac.mm

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/renderer_host/render_widget_host_view_mac.h"
 
 #include <QuartzCore/QuartzCore.h>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
@@ skipping 47 matching lines @@
 using content::RenderViewHostImpl;
 using content::RenderWidgetHostImpl;
 using content::RenderWidgetHostViewMac;
 using content::RenderWidgetHostViewMacEditCommandHelper;
 using WebKit::WebInputEvent;
 using WebKit::WebInputEventFactory;
 using WebKit::WebMouseEvent;
 using WebKit::WebMouseWheelEvent;
 using WebKit::WebGestureEvent;
 
+// These are not documented, so use only after checking -respondsToSelector:.
+@interface NSApplication (UndocumentedSpeechMethods)
+- (void)speakString:(NSString*)string;
+- (void)stopSpeaking:(id)sender;
+- (BOOL)isSpeaking;
+@end
+
 // Declare things that are part of the 10.7 SDK.
 #if !defined(MAC_OS_X_VERSION_10_7) || \
     MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_7
 @interface NSEvent (LionAPI)
 + (id)addLocalMonitorForEventsMatchingMask:(NSEventMask)mask
                                    handler:(NSEvent* (^)(NSEvent*))block;
 + (void)removeMonitor:(id)eventMonitor;
 @end
 
 @interface NSScreen (LionAPI)
@@ skipping 661 matching lines @@
     // set it again every single time the mouse moves.
     string16 display_text = tooltip_text_;
     if (tooltip_text_.length() > kMaxTooltipLength)
       display_text = tooltip_text_.substr(0, kMaxTooltipLength);
 
     NSString* tooltip_nsstring = base::SysUTF16ToNSString(display_text);
     [cocoa_view_ setToolTipAtMousePoint:tooltip_nsstring];
   }
 }
 
+bool RenderWidgetHostViewMac::SupportsSpeech() const {
+  return [NSApp respondsToSelector:@selector(speakString:)] &&
+         [NSApp respondsToSelector:@selector(stopSpeaking:)];
+}
+
+void RenderWidgetHostViewMac::SpeakSelection() {
+  // No need to check -respondsToSelect: because -validateUserInterfaceItem:
+  // validates this before enabling the item.
+  [NSApp speakString:base::SysUTF8ToNSString(selected_text_)];
+}
+
+bool RenderWidgetHostViewMac::IsSpeaking() const {
+  return [NSApp respondsToSelector:@selector(isSpeaking)] &&
+         [NSApp isSpeaking];
+}
+
+void RenderWidgetHostViewMac::StopSpeaking() {
+  // No need to check -respondsToSelect: because -validateUserInterfaceItem:
+  // validates this before enabling the item.

[Nico, 2012/08/06 15:47:31]

With this now being a public method, you probably should just check instead of
having this comment.

[Alexei Svitkine (slow), 2012/08/06 16:30:42]

Done.

+  [NSApp stopSpeaking:cocoa_view_];
+}
+
 //
 // RenderWidgetHostViewCocoa uses the stored selection text,
 // which implements NSServicesRequests protocol.
 //
 void RenderWidgetHostViewMac::SelectionChanged(const string16& text,
                                                size_t offset,
                                                const ui::Range& range) {
   if (range.is_empty() || text.empty()) {
       selected_text_.clear();
   } else {
@@ skipping 1574 matching lines @@
       @selector(validateUserInterfaceItem:isValidItem:)]) {
     BOOL valid;
     BOOL known = [delegate_ validateUserInterfaceItem:item
                                           isValidItem:&valid];
     if (known)
       return valid;
   }
 
   SEL action = [item action];
 
+  if (action == @selector(stopSpeaking:)) {
+    return renderWidgetHostView_->render_widget_host_->IsRenderView() &&
+           renderWidgetHostView_->IsSpeaking();
+  }
+  if (action == @selector(startSpeaking:)) {
+    return renderWidgetHostView_->render_widget_host_->IsRenderView() &&
+           renderWidgetHostView_->SupportsSpeech();
+  }
+
   // For now, these actions are always enabled for render view,
   // this is sub-optimal.
   // TODO(suzhe): Plumb the "can*" methods up from WebCore.
   if (action == @selector(undo:) ||
       action == @selector(redo:) ||
       action == @selector(cut:) ||
       action == @selector(copy:) ||
       action == @selector(copyToFindPboard:) ||
       action == @selector(paste:) ||
       action == @selector(pasteAndMatchStyle:)) {
@@ skipping 711 matching lines @@
   }
 }
 
 - (void)pasteAndMatchStyle:(id)sender {
   if (renderWidgetHostView_->render_widget_host_->IsRenderView()) {
     static_cast<RenderViewHostImpl*>(
         renderWidgetHostView_->render_widget_host_)->PasteAndMatchStyle();
   }
 }
 
+- (void)startSpeaking:(id)sender {
+  renderWidgetHostView_->SpeakSelection();
+}
+
+- (void)stopSpeaking:(id)sender {
+  renderWidgetHostView_->StopSpeaking();
+}
+
 - (void)cancelComposition {
   if (!hasMarkedText_)
     return;
 
   // Cancel the ongoing composition. [NSInputManager markedTextAbandoned:]
   // doesn't call any NSTextInput functions, such as setMarkedText or
   // insertText. So, we need to send an IPC message to a renderer so it can
   // delete the composition node.
   NSInputManager *currentInputManager = [NSInputManager currentInputManager];
   [currentInputManager markedTextAbandoned:self];
@@ skipping 131 matching lines @@
   if (!string) return NO;
 
   // If the user is currently using an IME, confirm the IME input,
   // and then insert the text from the service, the same as TextEdit and Safari.
   [self confirmComposition];
   [self insertText:string];
   return YES;
 }
 
 @end