Store and load icudtl.dat directly from the apk rather than extracting on start-up

chrome/browser/chrome_content_browser_client.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 "chrome/browser/chrome_content_browser_client.h"
 
 #include <set>
 #include <utility>
 #include <vector>
 
@@ skipping 156 matching lines @@
 #include "chrome/browser/chrome_browser_main_posix.h"
 #endif
 
 #if defined(OS_POSIX) && !defined(OS_MACOSX)
 #include "base/debug/leak_annotations.h"
 #include "components/crash/app/breakpad_linux.h"
 #include "components/crash/browser/crash_handler_host_linux.h"
 #endif
 
 #if defined(OS_ANDROID)
+#include "base/android/apk_assets.h"
 #include "ui/base/ui_base_paths.h"
 #include "ui/gfx/android/device_display_info.h"
 #endif
 
 #if defined(TOOLKIT_VIEWS)
 #include "chrome/browser/ui/views/chrome_browser_main_extra_parts_views.h"
 #endif
 
 #if defined(USE_ASH)
 #include "chrome/browser/ui/views/ash/chrome_browser_main_extra_parts_ash.h"
@@ skipping 2029 matching lines @@
   for (size_t i = 0; i < extra_parts_.size(); ++i) {
     extra_parts_[i]->GetAdditionalFileSystemBackends(
         browser_context, storage_partition_path, additional_backends);
   }
 }
 
 #if defined(OS_POSIX) && !defined(OS_MACOSX)
 void ChromeContentBrowserClient::GetAdditionalMappedFilesForChildProcess(
     const base::CommandLine& command_line,
     int child_process_id,
-    FileDescriptorInfo* mappings) {
+    FileDescriptorInfo* mappings
+#if defined(OS_ANDROID)
+    ,
+    std::map<int, base::MemoryMappedFile::Region>* regions
+#endif
+    ) {
 #if defined(V8_USE_EXTERNAL_STARTUP_DATA)
   if (v8_natives_fd_.get() == -1 || v8_snapshot_fd_.get() == -1) {
     int v8_natives_fd = -1;
     int v8_snapshot_fd = -1;
     if (gin::V8Initializer::OpenV8FilesForChildProcesses(&v8_natives_fd,
                                                          &v8_snapshot_fd)) {
       v8_natives_fd_.reset(v8_natives_fd);
       v8_snapshot_fd_.reset(v8_snapshot_fd);
     }
   }
@@ skipping 35 matching lines @@
                child_process_id);
     if (file.IsValid()) {
       mappings->Transfer(kAndroidMinidumpDescriptor,
                          base::ScopedFD(file.TakePlatformFile()));
     } else {
       LOG(ERROR) << "Failed to create file for minidump, crash reporting will "
                  "be disabled for this process.";
     }
   }
 
-  base::FilePath app_data_path;
-  PathService::Get(base::DIR_ANDROID_APP_DATA, &app_data_path);
-  DCHECK(!app_data_path.empty());
+  if (!icudtl_fd_.is_valid()) {
+    icudtl_fd_.reset(base::android::OpenApkAsset(base::i18n::kIcuDataFileName,
+          &icudtl_region_));
+    DCHECK(icudtl_fd_.is_valid());
+  }
+  mappings->Share(kAndroidICUDataDescriptor, icudtl_fd_.get());
+  regions->insert(std::make_pair(kAndroidICUDataDescriptor, icudtl_region_));

[jam, 2015/06/04 03:13:30]

why is chrome layer doing this instead of content layer? content knows about ICU

[agrieve, 2015/06/04 19:17:20]

I'm new to this code, and have no idea. I do know content still is the one to
use the FD that's opened here. Maybe the authors wanted to keep all
renderer-related file opens in one spot?

[jam, 2015/06/09 01:12:46]

Hi, please work with someone on the android side to figure out if this can be
done in content and not in chrome.

[Yaron, 2015/06/09 03:39:40]

Hmm. I definitely touched the crash fd code and it had to be done in chrome
layer because content doesn't deal with breakpad. I'm pretty sure that predated
the ICU fd passing and they probably just mirrored crash. I can take a deeper
look when I'm in tomorrow. 

 
-  flags = base::File::FLAG_OPEN | base::File::FLAG_READ;
-  base::FilePath icudata_path =
-      app_data_path.AppendASCII(base::i18n::kIcuDataFileName);
-  base::File icudata_file(icudata_path, flags);
-  DCHECK(icudata_file.IsValid());
-  mappings->Transfer(kAndroidICUDataDescriptor,
-                     base::ScopedFD(icudata_file.TakePlatformFile()));
 #else
   int crash_signal_fd = GetCrashSignalFD(command_line);
   if (crash_signal_fd >= 0) {
     mappings->Share(kCrashDumpSignal, crash_signal_fd);
   }
 #endif  // defined(OS_ANDROID)
 }
 #endif  // defined(OS_POSIX) && !defined(OS_MACOSX)
 
 #if defined(OS_WIN)
@@ skipping 143 matching lines @@
       switches::kDisableWebRtcEncryption,
     };
     to_command_line->CopySwitchesFrom(from_command_line,
                                       kWebRtcDevSwitchNames,
                                       arraysize(kWebRtcDevSwitchNames));
   }
 }
 #endif  // defined(ENABLE_WEBRTC)
 
 }  // namespace chrome