Let ImeAdapterAndroid have the same lifecycle as its Java peer

content/browser/renderer_host/ime_adapter_android.cc

Index: content/browser/renderer_host/ime_adapter_android.cc
diff --git a/content/browser/renderer_host/ime_adapter_android.cc b/content/browser/renderer_host/ime_adapter_android.cc
index bb8a938a2b37f261362f96e56819d518d5ee921f..3780fa8b16135f397cb7f86655d0b0ccd4fefd58 100644
--- a/content/browser/renderer_host/ime_adapter_android.cc
+++ b/content/browser/renderer_host/ime_adapter_android.cc
@@ -31,6 +31,8 @@
 using base::android::AttachCurrentThread;
 using base::android::ConvertJavaStringToUTF16;
 using base::android::JavaParamRef;
+using base::android::ScopedJavaLocalRef;
+using base::WeakPtr;
 
 namespace content {
 namespace {
@@ -63,6 +65,11 @@ bool RegisterImeAdapter(JNIEnv* env) {
   return RegisterNativesImpl(env);
 }
 
+jlong Init(JNIEnv* env, const JavaParamRef<jobject>& obj) {
+  ImeAdapterAndroid* adapter = new ImeAdapterAndroid(env, obj);
+  return reinterpret_cast<intptr_t>(adapter);
+}
+
 // Callback from Java to convert BackgroundColorSpan data to a
 // blink::WebCompositionUnderline instance, and append it to |underlines_ptr|.
 void AppendBackgroundColorSpan(JNIEnv*,
@@ -105,16 +112,28 @@ void AppendUnderlineSpan(JNIEnv*,
                                      SK_ColorTRANSPARENT));
 }
 
-ImeAdapterAndroid::ImeAdapterAndroid(RenderWidgetHostViewAndroid* rwhva)
-    : rwhva_(rwhva) {
-  DCHECK(rwhva_);
+ImeAdapterAndroid::ImeAdapterAndroid(JNIEnv* env,
+                                     const JavaParamRef<jobject>& obj) {
+  java_ime_adapter_ = JavaObjectWeakGlobalRef(env, obj);
 }
 
-ImeAdapterAndroid::~ImeAdapterAndroid() {
+void ImeAdapterAndroid::Destroy(JNIEnv* env, const JavaParamRef<jobject>& obj) {
+  delete this;
+}
+
+void ImeAdapterAndroid::SetRenderWidgetHostViewAndroid(
+    const WeakPtr<RenderWidgetHostViewAndroid> rwhva) {
+  rwhva_.reset();
+  rwhva_ = rwhva;
   JNIEnv* env = AttachCurrentThread();
-  base::android::ScopedJavaLocalRef<jobject> obj = java_ime_adapter_.get(env);
+  ScopedJavaLocalRef<jobject> obj = java_ime_adapter_.get(env);
   if (!obj.is_null())
-    Java_ImeAdapter_detach(env, obj);
+    Java_ImeAdapter_onConnectedToRenderProcess(env, obj);
+}
+
+ImeAdapterAndroid::~ImeAdapterAndroid() {
+  if (rwhva_)
+    rwhva_->ConnectImeAdapter(nullptr);
 }
 
 bool ImeAdapterAndroid::SendKeyEvent(
@@ -128,6 +147,8 @@ bool ImeAdapterAndroid::SendKeyEvent(
     int scan_code,
     bool is_system_key,
     int unicode_char) {
+  if (!rwhva_)
+    return false;
   NativeWebKeyboardEvent event = NativeWebKeyboardEventFromKeyEvent(
       env, original_key_event, type, modifiers, time_ms, key_code, scan_code,
       is_system_key, unicode_char);
@@ -200,25 +221,18 @@ void ImeAdapterAndroid::FinishComposingText(JNIEnv* env,
   rwhi->ImeFinishComposingText(true);
 }
 
-void ImeAdapterAndroid::AttachImeAdapter(
-    JNIEnv* env,
-    const JavaParamRef<jobject>& java_object) {
-  java_ime_adapter_ = JavaObjectWeakGlobalRef(env, java_object);
-}
-
 void ImeAdapterAndroid::CancelComposition() {
-  base::android::ScopedJavaLocalRef<jobject> obj =
-      java_ime_adapter_.get(AttachCurrentThread());
+  JNIEnv* env = AttachCurrentThread();
+  ScopedJavaLocalRef<jobject> obj = java_ime_adapter_.get(env);
   if (!obj.is_null())
-    Java_ImeAdapter_cancelComposition(AttachCurrentThread(), obj);
+    Java_ImeAdapter_cancelComposition(env, obj);
 }
 
 void ImeAdapterAndroid::FocusedNodeChanged(bool is_editable_node) {
-  base::android::ScopedJavaLocalRef<jobject> obj =
-      java_ime_adapter_.get(AttachCurrentThread());
+  JNIEnv* env = AttachCurrentThread();
+  ScopedJavaLocalRef<jobject> obj = java_ime_adapter_.get(env);
   if (!obj.is_null()) {
-    Java_ImeAdapter_focusedNodeChanged(AttachCurrentThread(), obj,
-                                       is_editable_node);
+    Java_ImeAdapter_focusedNodeChanged(env, obj, is_editable_node);
   }
 }
 
@@ -238,7 +252,7 @@ void ImeAdapterAndroid::SetEditableSelectionOffsets(
 void ImeAdapterAndroid::SetCharacterBounds(
     const std::vector<gfx::RectF>& character_bounds) {
   JNIEnv* env = AttachCurrentThread();
-  base::android::ScopedJavaLocalRef<jobject> obj = java_ime_adapter_.get(env);
+  ScopedJavaLocalRef<jobject> obj = java_ime_adapter_.get(env);
   if (obj.is_null())
     return;
 
@@ -316,14 +330,9 @@ void ImeAdapterAndroid::RequestCursorUpdate(
       rwhi->GetRoutingID(), immediate_request, monitor_request));
 }
 
-void ImeAdapterAndroid::ResetImeAdapter(JNIEnv* env,
-                                        const JavaParamRef<jobject>&) {
-  java_ime_adapter_.reset();
-}
-
 RenderWidgetHostImpl* ImeAdapterAndroid::GetFocusedWidget() {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
-  return rwhva_->GetFocusedWidget();
+  return rwhva_ ? rwhva_->GetFocusedWidget() : nullptr;

[boliu, 2017/03/23 04:17:01]

changwan: does everything here run on the UI thread? weakptrs are not thread
safe

[Jinsuk Kim, 2017/03/23 07:25:10]

I read that everything runs on UI thread. ThreadedInputConnection which runs on
IME thread posts every request onto UI thread before reaching here(I guess the
missing DCHECK for UI thread in |::SendKeyEvent| is just a mistake). But I'll
wait for changwan@ to confirm.

[Changwan Ryu, 2017/03/23 23:45:19]

Correct. Everything from ThreadedInput* to ImeAdapter should be on UI thread.
One exception is updateSelection() which goes directly to Android framework.

[Jinsuk Kim, 2017/03/24 02:34:23]

Thanks!

 }
 
 RenderFrameHost* ImeAdapterAndroid::GetFocusedFrame() {
@@ -331,6 +340,8 @@ RenderFrameHost* ImeAdapterAndroid::GetFocusedFrame() {
   // We get the focused frame from the WebContents of the page. Although
   // |rwhva_->GetFocusedWidget()| does a similar thing, there is no direct way
   // to get a RenderFrameHost from its RWH.
+  if (!rwhva_)
+    return nullptr;
   RenderWidgetHostImpl* rwh =
       RenderWidgetHostImpl::From(rwhva_->GetRenderWidgetHost());
   if (!rwh || !rwh->delegate())