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

base/i18n/icu_util.cc

Index: base/i18n/icu_util.cc
diff --git a/base/i18n/icu_util.cc b/base/i18n/icu_util.cc
index a9f0b129633cd596934b8cf7d680d1fcca7f7a8a..3e8e0cf47ff728bbcc2235cc9855ad85aa0fcbcb 100644
--- a/base/i18n/icu_util.cc
+++ b/base/i18n/icu_util.cc
@@ -23,6 +23,10 @@
 #include "third_party/icu/source/i18n/unicode/timezone.h"
 #endif
 
+#if defined(OS_ANDROID)
+#include "base/android/apk_assets.h"
+#endif
+
 #if defined(OS_MACOSX)
 #include "base/mac/foundation_util.h"
 #endif
@@ -38,7 +42,11 @@ namespace i18n {
 // No need to change the filename in multiple places (gyp files, windows
 // build pkg configurations, etc). 'l' stands for Little Endian.
 // This variable is exported through the header file.
+#if defined(OS_ANDROID)
+const char kIcuDataFileName[] = "assets/icudtl.dat";
+#else
 const char kIcuDataFileName[] = "icudtl.dat";
+#endif  // defined(OS_ANDROID)
 #if ICU_UTIL_DATA_IMPL == ICU_UTIL_DATA_SHARED
 #define ICU_UTIL_DATA_SYMBOL "icudt" U_ICU_VERSION_SHORT "_dat"
 #if defined(OS_WIN)
@@ -47,27 +55,19 @@ const char kIcuDataFileName[] = "icudtl.dat";
 #endif
 
 namespace {
-
+#if !defined(OS_NACL)
 #if !defined(NDEBUG)
 // Assert that we are not called more than once.  Even though calling this
 // function isn't harmful (ICU can handle it), being called twice probably
 // indicates a programming error.
-#if !defined(OS_NACL)
-bool g_called_once = false;
-#endif
 bool g_check_called_once = true;
-#endif
-}
+bool g_called_once = false;
+#endif  // !defined(NDEBUG)
 
-#if !defined(OS_NACL)
-bool InitializeICUWithFileDescriptor(
+
+bool InitializeICUWithFileDescriptorInternal(
     PlatformFile data_fd,
     MemoryMappedFile::Region data_region) {
-#if !defined(NDEBUG)
-  DCHECK(!g_check_called_once || !g_called_once);
-  g_called_once = true;
-#endif
-
 #if (ICU_UTIL_DATA_IMPL == ICU_UTIL_DATA_STATIC)
   // The ICU data is statically linked.
   return true;
@@ -84,7 +84,20 @@ bool InitializeICUWithFileDescriptor(
   return err == U_ZERO_ERROR;
 #endif // ICU_UTIL_DATA_FILE
 }
+#endif  // !defined(OS_NACL)
+
+}  // namespace
 
+#if !defined(OS_NACL)
+bool InitializeICUWithFileDescriptor(
+    PlatformFile data_fd,
+    MemoryMappedFile::Region data_region) {
+#if !defined(NDEBUG)
+  DCHECK(!g_check_called_once || !g_called_once);
+  g_called_once = true;
+#endif
+  return InitializeICUWithFileDescriptorInternal(data_fd, data_region);
+}
 
 bool InitializeICU() {
 #if !defined(NDEBUG)
@@ -118,7 +131,12 @@ bool InitializeICU() {
 #elif (ICU_UTIL_DATA_IMPL == ICU_UTIL_DATA_STATIC)
   // The ICU data is statically linked.
   result = true;
-#elif (ICU_UTIL_DATA_IMPL == ICU_UTIL_DATA_FILE)
+#elif (ICU_UTIL_DATA_IMPL == ICU_UTIL_DATA_FILE) && defined(OS_ANDROID)
+  base::MemoryMappedFile::Region region;
+  int fd = base::android::OpenApkAsset(kIcuDataFileName, &region);
+  CHECK_GE(fd, 0);
+  result = InitializeICUWithFileDescriptorInternal(fd, region);
+#elif (ICU_UTIL_DATA_IMPL == ICU_UTIL_DATA_FILE) && !defined(OS_ANDROID)
   // If the ICU data directory is set, ICU won't actually load the data until
   // it is needed.  This can fail if the process is sandboxed at that time.
   // Instead, we map the file in and hand off the data so the sandbox won't
@@ -137,8 +155,6 @@ bool InitializeICU() {
     wcscpy_s(tmp_buffer, data_path.value().c_str());
     debug::Alias(tmp_buffer);
     CHECK(path_ok);  // TODO(scottmg): http://crbug.com/445616
-#elif defined(OS_ANDROID)
-    bool path_ok = PathService::Get(DIR_ANDROID_APP_DATA, &data_path);
 #else
     // For now, expect the data file to be alongside the executable.
     // This is sufficient while we work on unit tests, but will eventually
@@ -193,10 +209,10 @@ bool InitializeICU() {
 #endif
   return result;
 }
-#endif
+#endif  // !defined(OS_NACL)
 
 void AllowMultipleInitializeCallsForTesting() {
-#if !defined(NDEBUG)
+#if !defined(NDEBUG) && !defined(OS_NACL)
   g_check_called_once = false;
 #endif
 }