[Android] Implement WebSettings.setAppCache{Enabled|Path}

content/browser/android/content_settings.cc

 // 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.
 
 #include "content/browser/android/content_settings.h"
 
 #include "base/android/jni_android.h"
 #include "base/android/jni_string.h"
 #include "content/browser/android/content_view_core_impl.h"
 #include "content/browser/renderer_host/render_view_host_delegate.h"
@@ skipping 60 matching lines @@
     java_script_enabled =
         GetFieldID(env, clazz, "mJavaScriptEnabled", "Z");
     allow_universal_access_from_file_urls =
         GetFieldID(env, clazz, "mAllowUniversalAccessFromFileURLs", "Z");
     allow_file_access_from_file_urls =
         GetFieldID(env, clazz, "mAllowFileAccessFromFileURLs", "Z");
     java_script_can_open_windows_automatically =
         GetFieldID(env, clazz, "mJavaScriptCanOpenWindowsAutomatically", "Z");
     support_multiple_windows =
         GetFieldID(env, clazz, "mSupportMultipleWindows", "Z");
+    app_cache_enabled =
+        GetFieldID(env, clazz, "mAppCacheEnabled", "Z");
+    app_cache_path =
+        GetFieldID(env, clazz, "mAppCachePath", kStringClassName);
     dom_storage_enabled =
         GetFieldID(env, clazz, "mDomStorageEnabled", "Z");
   }
 
   // Field ids
   jfieldID text_size_percent;
   jfieldID standard_fond_family;
   jfieldID fixed_font_family;
   jfieldID sans_serif_font_family;
   jfieldID serif_font_family;
   jfieldID cursive_font_family;
   jfieldID fantasy_font_family;
   jfieldID default_text_encoding;
   jfieldID user_agent;
   jfieldID minimum_font_size;
   jfieldID minimum_logical_font_size;
   jfieldID default_font_size;
   jfieldID default_fixed_font_size;
   jfieldID load_images_automatically;
   jfieldID images_enabled;
   jfieldID java_script_enabled;
   jfieldID allow_universal_access_from_file_urls;
   jfieldID allow_file_access_from_file_urls;
   jfieldID java_script_can_open_windows_automatically;
   jfieldID support_multiple_windows;
+  jfieldID app_cache_enabled;
+  jfieldID app_cache_path;
   jfieldID dom_storage_enabled;
 };
 
 ContentSettings::ContentSettings(JNIEnv* env,
                          jobject obj,
                          WebContents* contents,
                          bool is_master_mode)
     : WebContentsObserver(contents),
       is_master_mode_(is_master_mode),
       content_settings_(env, obj) {
@@ skipping 125 matching lines @@
 
   env->SetBooleanField(
       obj,
       field_ids_->support_multiple_windows,
       prefs.supports_multiple_windows);
   CheckException(env);
 
   Java_ContentSettings_setPluginsDisabled(env, obj, !prefs.plugins_enabled);
   CheckException(env);
 
+  // We don't need to sync AppCache settings to Java, because there are
+  // no getters for them in the API.
+
   env->SetBooleanField(
       obj,
       field_ids_->dom_storage_enabled,
       prefs.local_storage_enabled);
   CheckException(env);
 }
 
 void ContentSettings::SyncToNativeImpl() {
   JNIEnv* env = base::android::AttachCurrentThread();
   CHECK(env);
@@ skipping 83 matching lines @@
       obj, field_ids_->allow_file_access_from_file_urls);
 
   prefs.javascript_can_open_windows_automatically = env->GetBooleanField(
       obj, field_ids_->java_script_can_open_windows_automatically);
 
   prefs.supports_multiple_windows = env->GetBooleanField(
       obj, field_ids_->support_multiple_windows);
 
   prefs.plugins_enabled = !Java_ContentSettings_getPluginsDisabled(env, obj);
 
+  // AppCachePath is a global setting across all WebViews.
+  CR_DEFINE_STATIC_LOCAL(std::string, app_cache_path, ());

[boliu, 2012/11/30 17:46:27]

This is only global in WebViews, not inside webkit, right?

[joth, 2012/11/30 22:16:59]

also consider:
- CR_DEFINE_STATIC_LOCAL is not thread safe (neither construction of the global
or usage of it).
- use a different name to the FieldId member, to make this easier to read.
(g_app_cache_path would be reasonable).
- you only seem to be using this as a bool, so having a static bool maybe
simpler.
- I think all this patch is only needed for webview, so could we just implement
it in AwSettings? e.g. just put the policy we want right there on the java side?

[mnaganov (inactive), 2012/12/03 15:07:36]

I know it's not thread safe, but I was supposing that our gross synchronization
code serializes calls to SyncToNative, because they all go through the UI thread
and are invoked via message loops.

But I agree with your other considerations, and I have moved the code into the
Java side.

[mnaganov (inactive), 2012/12/03 15:07:36]

The cache storage is global in WebKit, see ApplicationCacheStorage.cpp

+  if (app_cache_path.empty()) {
+    str.Reset(
+        env, static_cast<jstring>(
+            env->GetObjectField(obj, field_ids_->app_cache_path)));
+    if (!str.is_null()) {
+      app_cache_path = ConvertJavaStringToUTF8(str);
+      // Java side should never set an empty string for the AppCache path.
+      DCHECK(!app_cache_path.empty());
+    }
+  }
+  prefs.application_cache_enabled =
+      !app_cache_path.empty() && env->GetBooleanField(
+          obj, field_ids_->app_cache_enabled);
+
   prefs.local_storage_enabled = env->GetBooleanField(
       obj, field_ids_->dom_storage_enabled);
 
   render_view_host->UpdateWebkitPreferences(prefs);
 }
 
 void ContentSettings::SyncFromNative(JNIEnv* env, jobject obj) {
   SyncFromNativeImpl();
 }
 
@@ skipping 19 matching lines @@
       new ContentSettings(env, obj, web_contents, is_master_mode);
   return reinterpret_cast<jint>(content_settings);
 }
 
 static jstring GetDefaultUserAgent(JNIEnv* env, jclass clazz) {
   return base::android::ConvertUTF8ToJavaString(
       env, GetContentClient()->GetUserAgent()).Release();
 }
 
 }  // namespace content