Allow startup with missing V8 snapshot file.

content/browser/child_process_launcher.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/child_process_launcher.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/files/file_util.h"
 #include "base/logging.h"
@@ skipping 130 matching lines @@
 #endif
 
 #if defined(OS_ANDROID)
   // Android WebView runs in single process, ensure that we never get here
   // when running in single process mode.
   CHECK(!cmd_line->HasSwitch(switches::kSingleProcess));
 
   GetContentClient()->browser()->GetAdditionalMappedFilesForChildProcess(
       *cmd_line, child_process_id, files_to_register.get());
 
+  GetContentClient()->browser()->AppendMappedFileCommandLineSwitches(cmd_line);
+
   StartChildProcess(
       cmd_line->argv(), child_process_id, files_to_register.Pass(),
       base::Bind(&OnChildProcessStartedAndroid, callback, client_thread_id,
                  begin_launch_time, base::Passed(&ipcfd)));
 
 #elif defined(OS_POSIX)
   // We need to close the client end of the IPC channel to reliably detect
   // child termination.
 
 #if !defined(OS_MACOSX)
   GetContentClient()->browser()->GetAdditionalMappedFilesForChildProcess(
       *cmd_line, child_process_id, files_to_register.get());
+
+  GetContentClient()->browser()->AppendMappedFileCommandLineSwitches(cmd_line);

[rmcilroy, 2015/06/05 13:24:51]

nit - there is another call to GetAdditionalMappedFilesForChildProcess in
battery_monitor_integration_browsertest.cc - could you add the
AppendMappedFileCommandLineSwitches call there too please.

[Erik Corry Chromium.org, 2015/06/08 13:31:03]

In the end I didn't do this becasue the command line is const, and the call to
GetAdditionalMappedFilesForChildProcess is inside another implementation of
GetAdditionalMappedFilesForChildProcess, so the caller of the outer version can
be expected to call AppendMappedFileCommandLineSwitches

[rmcilroy, 2015/06/08 17:26:12]

Ahh well, if it works I guess this is fine.

+
   if (use_zygote) {
     base::ProcessHandle handle = ZygoteHostImpl::GetInstance()->ForkRequest(
         cmd_line->argv(), files_to_register.Pass(), process_type);
     process = base::Process(handle);
   } else
   // Fall through to the normal posix case below when we're not zygoting.
 #endif  // !defined(OS_MACOSX)
   {
     // Convert FD mapping to FileHandleMappingVector
     base::FileHandleMappingVector fds_to_map =
@@ skipping 320 matching lines @@
 }
 
 ChildProcessLauncher::Client* ChildProcessLauncher::ReplaceClientForTest(
     Client* client) {
   Client* ret = client_;
   client_ = client;
   return ret;
 }
 
 }  // namespace content