Adds extension events for custom dictionary load/change.

chrome/browser/chromeos/extensions/input_method_api.cc

Index: chrome/browser/chromeos/extensions/input_method_api.cc
diff --git a/chrome/browser/chromeos/extensions/input_method_api.cc b/chrome/browser/chromeos/extensions/input_method_api.cc
index 22e9f44fdb26686786015cdc0ac6c2ed5b4b7ef4..8dc478e48f5370e0e0ad53c2a336247ffb7884d8 100644
--- a/chrome/browser/chromeos/extensions/input_method_api.cc
+++ b/chrome/browser/chromeos/extensions/input_method_api.cc
@@ -7,6 +7,7 @@
 #include "base/command_line.h"
 #include "base/lazy_instance.h"
 #include "base/values.h"
+#include "chrome/browser/chromeos/extensions/dictionary_event_router.h"
 #include "chrome/browser/chromeos/extensions/input_method_event_router.h"
 #include "chrome/browser/chromeos/input_method/input_method_util.h"
 #include "chrome/browser/extensions/api/input_ime/input_ime_api.h"
@@ -157,12 +158,22 @@ ExtensionFunction::ResponseAction AddWordToDictionaryFunction::Run() {
 }
 
 // static
+const char InputMethodAPI::kOnDictionaryChanged[] =
+    "inputMethodPrivate.onDictionaryChanged";
+
+// static
+const char InputMethodAPI::kOnDictionaryLoaded[] =
+    "inputMethodPrivate.onDictionaryLoaded";
+
+// static
 const char InputMethodAPI::kOnInputMethodChanged[] =
     "inputMethodPrivate.onChanged";
 
 InputMethodAPI::InputMethodAPI(content::BrowserContext* context)
     : context_(context) {
   EventRouter::Get(context_)->RegisterObserver(this, kOnInputMethodChanged);
+  EventRouter::Get(context_)->RegisterObserver(this, kOnDictionaryChanged);
+  EventRouter::Get(context_)->RegisterObserver(this, kOnDictionaryLoaded);
   ExtensionFunctionRegistry* registry =
       ExtensionFunctionRegistry::GetInstance();
   registry->RegisterFunction<GetInputMethodConfigFunction>();
@@ -193,10 +204,18 @@ void InputMethodAPI::Shutdown() {
 
 void InputMethodAPI::OnListenerAdded(
     const extensions::EventListenerInfo& details) {
-  DCHECK(!input_method_event_router_.get());
-  input_method_event_router_.reset(

[bshe, 2015/03/09 13:16:39]

I am not familiar with the code. But could this function being called multiple
times? Looks like you changed the logic here when that happen. Especially for
multi profiles case, you might want to test if it still works.

[Peter Wen, 2015/03/09 14:56:08]

Thanks for the heads up. Shu, thoughts?

I changed it so this function is called every time a listener is added instead
of exactly once, but each of the event routers is only initialized once, like
the original. We don't add too many listeners, so I think there is very little
overhead.

-      new chromeos::ExtensionInputMethodEventRouter(context_));
-  EventRouter::Get(context_)->UnregisterObserver(this);

[bshe, 2015/03/09 13:16:39]

Looks like you removed the UnregisterObserver step in the new code path. Could
this be a problem? If not a problem, you can remove the comment at line 200 and
201.

[Peter Wen, 2015/03/09 14:56:08]

Done.

+  if (details.event_name == kOnInputMethodChanged) {
+    if (!input_method_event_router_.get()) {
+      input_method_event_router_.reset(
+          new chromeos::ExtensionInputMethodEventRouter(context_));
+    }
+  } else if (details.event_name == kOnDictionaryChanged ||
+             details.event_name == kOnDictionaryLoaded) {
+    if (!dictionary_event_router_.get()) {
+      dictionary_event_router_.reset(
+          new chromeos::ExtensionDictionaryEventRouter(context_));
+    }
+  }
 }
 
 static base::LazyInstance<BrowserContextKeyedAPIFactory<InputMethodAPI> >