Remove env() getter from JavaRef<>

    Due to threadsafety ambiguity, it's not generally safe to call env()
    on a random Ref you've been passed, so this removes the temptation.
    The useful LocalRef optimizations are retained though, just in that
    sub-class.

(upstreaming CL, cherrypicked cleanly)

BUG=
TEST=


Review URL: http://codereview.chromium.org/9584014

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@128204 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 12 insertions, 16 deletions

diff --git a/content/browser/renderer_host/java/java_bound_object.cc b/content/browser/renderer_host/java/java_bound_object.cc
index ce13300..a9f7920 100644
--- a/content/browser/renderer_host/java/java_bound_object.cc
+++ b/content/browser/renderer_host/java/java_bound_object.cc
@@ -691,21 +691,18 @@ NPObject* JavaBoundObject::Create(const JavaRef<jobject>& object) {
 }
 
 JavaBoundObject::JavaBoundObject(const JavaRef<jobject>& object)
-    : java_object_(object.env()->NewGlobalRef(object.obj())) {
+    : java_object_(object) {
   // We don't do anything with our Java object when first created. We do it all
   // lazily when a method is first invoked.
 }
 
 JavaBoundObject::~JavaBoundObject() {
-  // Use the current thread's JNI env to release our global ref to the Java
-  // object.
-  AttachCurrentThread()->DeleteGlobalRef(java_object_);
 }
 
 jobject JavaBoundObject::GetJavaObject(NPObject* object) {
   DCHECK_EQ(&JavaNPObject::kNPClass, object->_class);
   JavaBoundObject* jbo = reinterpret_cast<JavaNPObject*>(object)->bound_object;
-  return jbo->java_object_;
+  return jbo->java_object_.obj();
 }
 
 bool JavaBoundObject::HasMethod(const std::string& name) const {
@@ -746,8 +743,8 @@ bool JavaBoundObject::Invoke(const std::string& name, const NPVariant* args,
   }
 
   // Call
-  *result = CallJNIMethod(java_object_, method->return_type(), method->id(),
-                          &parameters[0]);
+  *result = CallJNIMethod(java_object_.obj(), method->return_type(),
+                          method->id(), &parameters[0]);
   return true;
 }
 
@@ -758,7 +755,7 @@ void JavaBoundObject::EnsureMethodsAreSetUp() const {
 
   JNIEnv* env = AttachCurrentThread();
   ScopedJavaLocalRef<jclass> clazz(env, static_cast<jclass>(
-      env->CallObjectMethod(java_object_,  GetMethodIDFromClassName(
+      env->CallObjectMethod(java_object_.obj(),  GetMethodIDFromClassName(
           env,
           kJavaLangObject,
           kGetClass,
diff --git a/content/browser/renderer_host/java/java_bound_object.h b/content/browser/renderer_host/java/java_bound_object.h
index 61a1dfb..cf0c403 100644
--- a/content/browser/renderer_host/java/java_bound_object.h
+++ b/content/browser/renderer_host/java/java_bound_object.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
@@ -44,10 +44,9 @@ class JavaBoundObject {
 
   void EnsureMethodsAreSetUp() const;
 
-  // Global ref to the underlying Java object. We use a naked jobject, rather
-  // than a ScopedJavaGlobalRef, as the global ref will be added and dropped on
-  // different threads.
-  jobject java_object_;
+  // The global ref to the underlying Java object that this JavaBoundObject
+  // instance represents.
+  base::android::ScopedJavaGlobalRef<jobject> java_object_;
 
   // Map of public methods, from method name to Method instance. Multiple
   // entries will be present for overloaded methods. Note that we can't use
diff --git a/content/browser/renderer_host/java/java_method.cc b/content/browser/renderer_host/java/java_method.cc
index 01235e8..6f6878c 100644
--- a/content/browser/renderer_host/java/java_method.cc
+++ b/content/browser/renderer_host/java/java_method.cc
@@ -95,7 +95,7 @@ JavaMethod::JavaMethod(const base::android::JavaRef<jobject>& method)
     : java_method_(method),
       have_calculated_num_parameters_(false),
       id_(NULL) {
-  JNIEnv* env = java_method_.env();
+  JNIEnv* env = AttachCurrentThread();
   // On construction, we do nothing except get the name. Everything else is
   // done lazily.
   ScopedJavaLocalRef<jstring> name(env, static_cast<jstring>(
@@ -139,7 +139,7 @@ void JavaMethod::EnsureNumParametersIsSetUp() const {
   // The number of parameters will be used frequently when determining
   // whether to call this method. We don't get the ID etc until actually
   // required.
-  JNIEnv* env = java_method_.env();
+  JNIEnv* env = AttachCurrentThread();
   ScopedJavaLocalRef<jarray> parameters(env, static_cast<jarray>(
       env->CallObjectMethod(java_method_.obj(), GetMethodIDFromClassName(
           env,
@@ -155,7 +155,7 @@ void JavaMethod::EnsureTypesAndIDAreSetUp() const {
   }
 
   // Get the parameters
-  JNIEnv* env = java_method_.env();
+  JNIEnv* env = AttachCurrentThread();
   ScopedJavaLocalRef<jobjectArray> parameters(env, static_cast<jobjectArray>(
       env->CallObjectMethod(java_method_.obj(), GetMethodIDFromClassName(
           env,