arc-bridge: Introduce the ArcService class

components/arc/ime/arc_ime_ipc_host.cc

Index: components/arc/ime/arc_ime_ipc_host.cc
diff --git a/components/arc/ime/arc_ime_ipc_host.cc b/components/arc/ime/arc_ime_ipc_host.cc
index 93fcef43325261c16d63b3e6512c797810bdcb04..86a3bc5b185097fbd07b1a4b63192716b02a2100 100644
--- a/components/arc/ime/arc_ime_ipc_host.cc
+++ b/components/arc/ime/arc_ime_ipc_host.cc
@@ -70,24 +70,33 @@ mojo::Array<arc::CompositionSegmentPtr> ConvertSegments(
 }  // namespace
 
 ArcImeIpcHost::ArcImeIpcHost(Delegate* delegate,
-                             ArcBridgeService* bridge_service)
-    : binding_(this), delegate_(delegate), bridge_service_(bridge_service) {
-  bridge_service_->AddObserver(this);
+                             ArcBridgeService* arc_bridge_service)
+    : arc_bridge_service_(arc_bridge_service),
+      binding_(this),
+      delegate_(delegate) {
+  DCHECK(arc_bridge_service_);
+  arc_bridge_service_->AddObserver(this);
+
+  // If ImeInstance was ready before we AddObserver(), we won't get
+  // OnImeInstanceReady events. For such case, we have to call it
+  // explicitly.
+  if (arc_bridge_service_->ime_instance())
+    OnImeInstanceReady();
 }
 
 ArcImeIpcHost::~ArcImeIpcHost() {
-  bridge_service_->RemoveObserver(this);
+  arc_bridge_service_->RemoveObserver(this);
 }
 
 void ArcImeIpcHost::OnImeInstanceReady() {
   arc::ImeHostPtr host;
   binding_.Bind(mojo::GetProxy(&host));
-  bridge_service_->ime_instance()->Init(std::move(host));
+  arc_bridge_service_->ime_instance()->Init(std::move(host));
 }
 
 void ArcImeIpcHost::SendSetCompositionText(
     const ui::CompositionText& composition) {
-  ImeInstance* ime_instance = bridge_service_->ime_instance();
+  ImeInstance* ime_instance = arc_bridge_service_->ime_instance();
   if (!ime_instance) {
     LOG(ERROR) << "ArcImeInstance method called before being ready.";
     return;
@@ -98,7 +107,7 @@ void ArcImeIpcHost::SendSetCompositionText(
 }
 
 void ArcImeIpcHost::SendConfirmCompositionText() {
-  ImeInstance* ime_instance = bridge_service_->ime_instance();
+  ImeInstance* ime_instance = arc_bridge_service_->ime_instance();
   if (!ime_instance) {
     LOG(ERROR) << "ArcImeInstance method called before being ready.";
     return;
@@ -108,7 +117,7 @@ void ArcImeIpcHost::SendConfirmCompositionText() {
 }
 
 void ArcImeIpcHost::SendInsertText(const base::string16& text) {
-  ImeInstance* ime_instance = bridge_service_->ime_instance();
+  ImeInstance* ime_instance = arc_bridge_service_->ime_instance();
   if (!ime_instance) {
     LOG(ERROR) << "ArcImeInstance method called before being ready.";
     return;