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

content/shell/browser/shell_content_browser_client.cc

Index: content/shell/browser/shell_content_browser_client.cc
diff --git a/content/shell/browser/shell_content_browser_client.cc b/content/shell/browser/shell_content_browser_client.cc
index 23535f386aa6d8b5a648e573ab5bae1e7c34ab19..2dd5095fec0e6c9a1c296cce8ecdb862e08c8e76 100644
--- a/content/shell/browser/shell_content_browser_client.cc
+++ b/content/shell/browser/shell_content_browser_client.cc
@@ -34,7 +34,6 @@
 #include "content/shell/common/shell_messages.h"
 #include "content/shell/common/shell_switches.h"
 #include "content/shell/renderer/layout_test/blink_test_helpers.h"
-#include "gin/v8_initializer.h"
 #include "net/url_request/url_request_context_getter.h"
 #include "url/gurl.h"
 
@@ -129,12 +128,7 @@ void ShellContentBrowserClient::SetSwapProcessesForRedirect(bool swap) {
 }
 
 ShellContentBrowserClient::ShellContentBrowserClient()
-    :
-#if defined(OS_POSIX) && !defined(OS_MACOSX)
-      v8_natives_fd_(-1),
-      v8_snapshot_fd_(-1),
-#endif  // OS_POSIX && !OS_MACOSX
-      shell_browser_main_parts_(NULL) {
+    : shell_browser_main_parts_(NULL) {
   DCHECK(!g_browser_client);
   g_browser_client = this;
 }
@@ -213,10 +207,13 @@ void ShellContentBrowserClient::AppendMappedFileCommandLineSwitches(
   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())
+    // V8 can't start up without the source of the natives, but it can
+    // start up (slower) without the snapshot.
+    if (v8_files_.snapshot_fd.is_valid()) {
       command_line->AppendSwitch(::switches::kV8SnapshotPassedByFD);
+    }
   }
 #endif  // V8_USE_EXTERNAL_STARTUP_DATA
 #endif  // OS_POSIX && !OS_MACOSX
@@ -353,22 +350,23 @@ void ShellContentBrowserClient::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)
   int flags = base::File::FLAG_OPEN | base::File::FLAG_READ;
   base::FilePath pak_file;