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..bdf41d86937d2fde518a67d083091ee172f284de 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
@@ -118,7 +122,16 @@ 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(fd != -1);

[Lei Zhang, 2015/06/02 20:31:15]

CHECK_GE(fd, 0);

+
+#if !defined(NDEBUG)
+  g_called_once = false;

[Lei Zhang, 2015/06/02 20:31:15]

Can you explain what's going on here?

[Yaron, 2015/06/02 21:19:40]

In comment or why this is happening? It was bugging me too (see other comments)
but it's needed to be unset because the next step is to call into
InitializeICUWithFileDescriptor which also checks the flag (to prevent
initializing twice).

The simplest fix might be to define helper *Internal versions of these functions
that are private. Then InitializeICU can call
InitializeICUWithFileDescriptorInternal and not have to unset the flag for
public API access.

+#endif
+  result = InitializeICUWithFileDescriptor(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 +150,6 @@ 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