[Android] Support startup histogram.

chrome/app/chrome_main_delegate.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 "chrome/app/chrome_main_delegate.h"
 
 #include "base/command_line.h"
 #include "base/files/file_path.h"
 #include "base/lazy_instance.h"
 #include "base/message_loop/message_loop.h"
@@ skipping 322 matching lines @@
 #endif  // OS_POSIX
 
 struct MainFunction {
   const char* name;
   int (*function)(const content::MainFunctionParams&);
 };
 
 }  // namespace
 
 ChromeMainDelegate::ChromeMainDelegate() {
+#if defined(OS_ANDROID)
+// On Android the main entry point time is the time when the Java code starts.
+// This happens before the shared library containing this code is even loaded.
+// The Java startup code has recorded that time, but the C++ code can't fetch it
+// from the Java side until it has initialized the JNI. See
+// ChromeMainDelegateAndroid.
+#else
   startup_metric_utils::RecordMainEntryPointTime();
+#endif
 }
 
 ChromeMainDelegate::~ChromeMainDelegate() {
 }
 
 bool ChromeMainDelegate::BasicStartupComplete(int* exit_code) {
 #if defined(OS_CHROMEOS)
   chromeos::BootTimesLoader::Get()->SaveChromeMainStats();
 #endif
 
@@ skipping 503 matching lines @@
 }
 
 content::ContentUtilityClient*
 ChromeMainDelegate::CreateContentUtilityClient() {
 #if defined(CHROME_MULTIPLE_DLL_BROWSER)
   return NULL;
 #else
   return &g_chrome_content_utility_client.Get();
 #endif
 }