Load non-locale .pak files directly from the .apk on Android (rather than extracting on start-up).

chromecast/app/cast_main_delegate.cc

 // Copyright 2014 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 "chromecast/app/cast_main_delegate.h"
 
 #include <string>
 
 #include "base/command_line.h"
 #include "base/cpu.h"
 #include "base/lazy_instance.h"
 #include "base/logging.h"
 #include "base/path_service.h"
 #include "base/posix/global_descriptors.h"
 #include "chromecast/base/cast_paths.h"
 #include "chromecast/browser/cast_content_browser_client.h"
 #include "chromecast/common/cast_resource_delegate.h"
 #include "chromecast/common/global_descriptors.h"
 #include "chromecast/crash/cast_crash_reporter_client.h"
 #include "chromecast/renderer/cast_content_renderer_client.h"
 #include "components/crash/app/crash_reporter_client.h"
 #include "content/public/browser/browser_main_runner.h"
 #include "content/public/common/content_switches.h"
 #include "ui/base/resource/resource_bundle.h"
 
 #if defined(OS_ANDROID)
+#include "base/android/apk_assets.h"
 #include "chromecast/crash/android/crash_handler.h"
 #endif  // defined(OS_ANDROID)
 
 namespace {
 
 #if !defined(OS_ANDROID)
 base::LazyInstance<chromecast::CastCrashReporterClient>::Leaky
     g_crash_reporter_client = LAZY_INSTANCE_INITIALIZER;
 #endif  // !defined(OS_ANDROID)
 
@@ skipping 85 matching lines @@
   std::string process_type =
       command_line->GetSwitchValueASCII(switches::kProcessType);
   CastCrashReporterClient::InitCrashReporter(process_type);
 }
 #endif  // !defined(OS_ANDROID)
 
 void CastMainDelegate::InitializeResourceBundle() {
 #if defined(OS_ANDROID)
   // On Android, the renderer runs with a different UID and can never access
   // the file system. Use the file descriptor passed in at launch time.
-  int pak_fd =
-      base::GlobalDescriptors::GetInstance()->MaybeGet(kAndroidPakDescriptor);
+  auto global_descriptors = base::GlobalDescriptors::GetInstance();
+  int pak_fd = global_descriptors->MaybeGet(kAndroidPakDescriptor);
+  base::MemoryMappedFile::Region pak_region;
   if (pak_fd >= 0) {
-    ui::ResourceBundle::InitSharedInstanceWithPakFileRegion(
-        base::File(pak_fd), base::MemoryMappedFile::Region::kWholeFile);
-    ui::ResourceBundle::GetSharedInstance().AddDataPackFromFile(
-        base::File(pak_fd), ui::SCALE_FACTOR_100P);
+    pak_region = global_descriptors->GetRegion(kAndroidPakDescriptor);
+    ui::ResourceBundle::InitSharedInstanceWithPakFileRegion(base::File(pak_fd),
+                                                            pak_region);
+    ui::ResourceBundle::GetSharedInstance().AddDataPackFromFileRegion(
+        base::File(pak_fd), pak_region, ui::SCALE_FACTOR_100P);
     return;
+  } else {
+    pak_fd = base::android::OpenApkAsset("assets/cast_shell.pak", &pak_region);
+    DCHECK_GE(pak_fd, 0);
+    global_descriptors->Set(kAndroidPakDescriptor, pak_fd, pak_region);
   }
 #endif  // defined(OS_ANDROID)
 
   resource_delegate_.reset(new CastResourceDelegate());
   // TODO(gunsch): Use LOAD_COMMON_RESOURCES once ResourceBundle no longer
   // hardcodes resource file names.
   ui::ResourceBundle::InitSharedInstanceWithLocale(
       "en-US",
       resource_delegate_.get(),
       ui::ResourceBundle::DO_NOT_LOAD_COMMON_RESOURCES);
 
+#if defined(OS_ANDROID)
+  ui::ResourceBundle::GetSharedInstance().AddDataPackFromFileRegion(
+      base::File(pak_fd), pak_region, ui::SCALE_FACTOR_NONE);
+#else
   base::FilePath pak_file;
   CHECK(PathService::Get(FILE_CAST_PAK, &pak_file));
   ui::ResourceBundle::GetSharedInstance().AddDataPackFromPath(
       pak_file,
       ui::SCALE_FACTOR_NONE);
+#endif  // defined(OS_ANDROID)
 }
 
 content::ContentBrowserClient* CastMainDelegate::CreateContentBrowserClient() {
   browser_client_ = CastContentBrowserClient::Create();
   return browser_client_.get();
 }
 
 content::ContentRendererClient*
 CastMainDelegate::CreateContentRendererClient() {
   renderer_client_ = CastContentRendererClient::Create();
   return renderer_client_.get();
 }
 
 }  // namespace shell
 }  // namespace chromecast