arc-bridge: Introduce the ArcService class

components/arc/clipboard/arc_clipboard_bridge.cc

Index: components/arc/clipboard/arc_clipboard_bridge.cc
diff --git a/components/arc/clipboard/arc_clipboard_bridge.cc b/components/arc/clipboard/arc_clipboard_bridge.cc
index 06e39fb4b5e2ccfe2b911ca21ba78ddf507e9a88..169869c0d113eed2a70680dccba97c12569e8606 100644
--- a/components/arc/clipboard/arc_clipboard_bridge.cc
+++ b/components/arc/clipboard/arc_clipboard_bridge.cc
@@ -27,18 +27,26 @@ static mojo::String ConvertString16ToMojoString(const base::string16& input) {
 
 namespace arc {
 
-ArcClipboardBridge::ArcClipboardBridge(ArcBridgeService* bridge_service)
-    : bridge_service_(bridge_service), binding_(this) {
-  bridge_service_->AddObserver(this);
+ArcClipboardBridge::ArcClipboardBridge(ArcBridgeService* arc_bridge_service)
+    : arc_bridge_service_(arc_bridge_service), binding_(this) {
+  DCHECK(arc_bridge_service_);
+  arc_bridge_service_->AddObserver(this);
+
+  // If ClipboardInstance was ready before we AddObserver(), we won't get
+  // OnClipboardInstanceReady events. For such case, we have to call it
+  // explicitly.
+  if (arc_bridge_service_->clipboard_instance())
+    OnClipboardInstanceReady();
 }
 
 ArcClipboardBridge::~ArcClipboardBridge() {
   DCHECK(CalledOnValidThread());
-  bridge_service_->RemoveObserver(this);
+  arc_bridge_service_->RemoveObserver(this);
 }
 
 void ArcClipboardBridge::OnClipboardInstanceReady() {
-  ClipboardInstance* clipboard_instance = bridge_service_->clipboard_instance();
+  ClipboardInstance* clipboard_instance =
+      arc_bridge_service_->clipboard_instance();
   if (!clipboard_instance) {
     LOG(ERROR) << "OnClipboardInstanceReady called, "
                << "but no clipboard instance found";
@@ -63,7 +71,8 @@ void ArcClipboardBridge::GetTextContent() {
   ui::Clipboard* clipboard = ui::Clipboard::GetForCurrentThread();
   clipboard->ReadText(ui::CLIPBOARD_TYPE_COPY_PASTE, &text);
 
-  ClipboardInstance* clipboard_instance = bridge_service_->clipboard_instance();
+  ClipboardInstance* clipboard_instance =
+      arc_bridge_service_->clipboard_instance();
   clipboard_instance->OnGetTextContent(ConvertString16ToMojoString(text));
 }