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

extensions/shell/browser/shell_content_browser_client.cc

Index: extensions/shell/browser/shell_content_browser_client.cc
diff --git a/extensions/shell/browser/shell_content_browser_client.cc b/extensions/shell/browser/shell_content_browser_client.cc
index d542a6792f29c796bf50746926b6c28a182750a2..a4a4345f489a96122a1e4d6123b25236d0f30611 100644
--- a/extensions/shell/browser/shell_content_browser_client.cc
+++ b/extensions/shell/browser/shell_content_browser_client.cc
@@ -28,7 +28,6 @@
 #include "extensions/shell/browser/shell_browser_main_parts.h"
 #include "extensions/shell/browser/shell_extension_system.h"
 #include "extensions/shell/browser/shell_speech_recognition_manager_delegate.h"
-#include "gin/v8_initializer.h"
 #include "url/gurl.h"
 
 #if !defined(DISABLE_NACL)
@@ -54,12 +53,7 @@ ShellContentBrowserClient* g_instance = nullptr;
 
 ShellContentBrowserClient::ShellContentBrowserClient(
     ShellBrowserMainDelegate* browser_main_delegate)
-    :
-#if defined(OS_POSIX) && !defined(OS_MACOSX)
-      v8_natives_fd_(-1),
-      v8_snapshot_fd_(-1),
-#endif  // OS_POSIX && !OS_MACOSX
-      browser_main_parts_(nullptr),
+    : browser_main_parts_(nullptr),
       browser_main_delegate_(browser_main_delegate) {
   DCHECK(!g_instance);
   g_instance = this;
@@ -202,15 +196,17 @@ void ShellContentBrowserClient::SiteInstanceDeleting(
 
 void ShellContentBrowserClient::AppendMappedFileCommandLineSwitches(
     base::CommandLine* command_line) {
-  std::string process_type =
-      command_line->GetSwitchValueASCII(::switches::kProcessType);
-
 #if defined(OS_POSIX) && !defined(OS_MACOSX)
 #if defined(V8_USE_EXTERNAL_STARTUP_DATA)
-  DCHECK(natives_fd_exists());
-  command_line->AppendSwitch(::switches::kV8NativesPassedByFD);
-  if (snapshot_fd_exists())
-    command_line->AppendSwitch(::switches::kV8SnapshotPassedByFD);
+  std::string process_type =
+      command_line->GetSwitchValueASCII(switches::kProcessType);
+  if (process_type != switches::kZygoteProcess) {
+    DCHECK(v8_files_.natives_fd.is_valid());
+    command_line->AppendSwitch(::switches::kV8NativesPassedByFD);
+    if (v8_files_.snapshot_fd.is_valid()) {
+      command_line->AppendSwitch(::switches::kV8SnapshotPassedByFD);
+    }
+  }
 #endif  // V8_USE_EXTERNAL_STARTUP_DATA
 #endif  // OS_POSIX && !OS_MACOSX
 }
@@ -264,20 +260,22 @@ 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)

[rmcilroy, 2015/06/09 11:52:54]

I don't think this needs to be #ifdef ANDROID - all other platforms should
return kWholeFile which will the be fine if passed to the LoadV8NativesFromFD.

+  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
 }
 #endif  // OS_POSIX && !OS_MACOSX