Load v8 snapshots directly from APK (and store them uncompressed)

chromecast/browser/cast_content_browser_client.cc

Index: chromecast/browser/cast_content_browser_client.cc
diff --git a/chromecast/browser/cast_content_browser_client.cc b/chromecast/browser/cast_content_browser_client.cc
index 124730bfdf6d9f4b022ef929077f836bffb4c079..99a8d508266d2c4c80edba48f084d37ac0d49748 100644
--- a/chromecast/browser/cast_content_browser_client.cc
+++ b/chromecast/browser/cast_content_browser_client.cc
@@ -38,7 +38,6 @@
 #include "content/public/common/content_switches.h"
 #include "content/public/common/url_constants.h"
 #include "content/public/common/web_preferences.h"
-#include "gin/v8_initializer.h"
 #include "media/audio/audio_manager_factory.h"
 #include "net/ssl/ssl_cert_request_info.h"
 #include "net/url_request/url_request_context_getter.h"
@@ -53,9 +52,7 @@ namespace chromecast {
 namespace shell {
 
 CastContentBrowserClient::CastContentBrowserClient()
-    : v8_natives_fd_(-1),
-      v8_snapshot_fd_(-1),
-      url_request_context_factory_(new URLRequestContextFactory()) {
+    : url_request_context_factory_(new URLRequestContextFactory()) {
 }
 
 CastContentBrowserClient::~CastContentBrowserClient() {
@@ -153,16 +150,19 @@ bool CastContentBrowserClient::IsHandledURL(const GURL& url) {
 
 void CastContentBrowserClient::AppendMappedFileCommandLineSwitches(
     base::CommandLine* command_line) {
-  std::string process_type =
-      command_line->GetSwitchValueNative(switches::kProcessType);
-
+#if defined(OS_POSIX) && !defined(OS_MACOSX)
 #if defined(V8_USE_EXTERNAL_STARTUP_DATA)
+  std::string process_type =
+      command_line->GetSwitchValueASCII(switches::kProcessType);
   if (process_type != switches::kZygoteProcess) {
-    DCHECK(natives_fd_exists());
+    DCHECK(v8_files_.natives_fd.is_valid());
     command_line->AppendSwitch(::switches::kV8NativesPassedByFD);
-    if (snapshot_fd_exists())
+    if (v8_files_.snapshot_fd.is_valid()) {
       command_line->AppendSwitch(::switches::kV8SnapshotPassedByFD);
+    }
   }
+#endif  // V8_USE_EXTERNAL_STARTUP_DATA
+#endif  // OS_POSIX && !OS_MACOSX
 }
 
 #endif  // V8_USE_EXTERNAL_STARTUP_DATA
@@ -332,20 +332,22 @@ void CastContentBrowserClient::GetAdditionalMappedFilesForChildProcess(
 #endif
     ) {
 #if defined(V8_USE_EXTERNAL_STARTUP_DATA)
-  if (!natives_fd_exists()) {
-    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);
-    }
+  if (!v8_files_.natives_fd.is_valid()) {
+    gin::V8Initializer::OpenV8FilesForChildProcesses(&v8_files_);
+  }
+  DCHECK(v8_files_.natives_fd.is_valid());
+  mappings->Share(kV8NativesDataDescriptor, v8_files_.natives_fd.get());
+#if defined(OS_ANDROID)
+  regions->insert(
+      std::make_pair(kV8NativesDataDescriptor, v8_files_.natives_region));
+#endif
+  if (v8_files_.snapshot_fd.is_valid()) {
+    mappings->Share(kV8SnapshotDataDescriptor, v8_files_.snapshot_fd.get());
+#if defined(OS_ANDROID)
+    regions->insert(
+        std::make_pair(kV8SnapshotDataDescriptor, v8_files_.snapshot_region));
+#endif
   }
-  // V8 can't start up without the source of the natives, but it can
-  // start up (slower) without the snapshot.
-  DCHECK(natives_fd_exists());
-  mappings->Share(kV8NativesDataDescriptor, v8_natives_fd_.get());
-  mappings->Share(kV8SnapshotDataDescriptor, v8_snapshot_fd_.get());
 #endif  // V8_USE_EXTERNAL_STARTUP_DATA
 #if defined(OS_ANDROID)
   const int flags_open_read = base::File::FLAG_OPEN | base::File::FLAG_READ;