[DevTools] Move DispatchOnDevToolsFrontend to embedder.

chrome/browser/devtools/devtools_ui_bindings.cc

Index: chrome/browser/devtools/devtools_ui_bindings.cc
diff --git a/chrome/browser/devtools/devtools_ui_bindings.cc b/chrome/browser/devtools/devtools_ui_bindings.cc
index e87b70a0f5533e5693e52b41b5467d94cfb46224..7441341915dcd449e82ca902afdac6ddc63a1b5b 100644
--- a/chrome/browser/devtools/devtools_ui_bindings.cc
+++ b/chrome/browser/devtools/devtools_ui_bindings.cc
@@ -409,8 +409,9 @@ void DevToolsUIBindings::HandleMessageFromDevToolsFrontendToBackend(
 // content::DevToolsClientHost implementation ---------------------------------
 void DevToolsUIBindings::DispatchOnInspectorFrontend(
     const std::string& message) {
-  if (frontend_host_)
-    frontend_host_->DispatchOnDevToolsFrontend(message);
+  base::StringValue message_value(message);
+  CallClientFunction("InspectorFrontendAPI.dispatchMessage",
+                     &message_value, NULL, NULL);
 }
 
 void DevToolsUIBindings::InspectedContentsClosing() {
@@ -796,8 +797,30 @@ void DevToolsUIBindings::CallClientFunction(const std::string& function_name,
       }
     }
   }
-  base::string16 javascript =
-      base::UTF8ToUTF16(function_name + "(" + params + ");");
+
+  std::string code = function_name + "(" + params + ");";
+#if defined(DEBUG_DEVTOOLS)
+  // To debug DevTools itself, we should postpone incoming messages while
+  // paused in debugger. To achieve this, we wrap all calls in setTimeout
+  // and rely on the fact that timers are suspended when debugging.
+  code = "(function() {"
+         "  if (!window.__callClientFunction) window.__callClientFunction = [];"

[pfeldman, 2014/07/31 14:25:08]

Should we do this on the front-end side instead?

[dgozman, 2014/07/31 15:09:32]

Done.

+         ""
+         "  function executeCall() {" + code + "}"
+         ""
+         "  function onTimeout() {"
+         "    while (window.__callClientFunction.length) {"
+         "      window.__callClientFunction.shift()();"
+         "    }"
+         "  }"
+         ""
+         "  window.__callClientFunction.push(executeCall);"
+         "  if (window.__callClientFunction.length == 1)"
+         "    window.setTimeout(onTimeout, 0);"
+         "})();";
+#endif  // defined(DEBUG_DEVTOOLS)
+
+  base::string16 javascript = base::UTF8ToUTF16(code);
   web_contents_->GetMainFrame()->ExecuteJavaScript(javascript);
 }