Turn the utility process image decoder into a Mojo service.

chrome/common/chrome_switches.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/common/chrome_switches.h"
 
 #include "base/base_switches.h"
 #include "base/command_line.h"
 
 namespace switches {
@@ skipping 259 matching lines @@
 // issues relating to IPv6, but shouldn't otherwise be needed. Be sure to file
 // bugs if something isn't working properly in the presence of IPv6. This flag
 // can be overidden by the "enable-ipv6" flag.
 const char kDisableIPv6[]                   = "disable-ipv6";
 
 // Disable the behavior that the second click on a launcher item (the click when
 // the item is already active) minimizes the item.
 const char kDisableMinimizeOnSecondLauncherItemClick[] =
     "disable-minimize-on-second-launcher-item-click";
 
+// Disable using Mojo for utility process services.
+const char kDisableMojoUtilityServices[] = "disable-mojo-utility-services";
+
 // Disables the new bookmark app system.
 const char kDisableNewBookmarkApps[]        = "disable-new-bookmark-apps";
 
 // Disables the new offline error page generated by NetErrorHelper for ChromeOS
 // and instead uses the old error page generated by OfflineResourceThrottle.
 const char kDisableNewOfflineErrorPage[] = "disable-new-offline-error-page";
 
 // Disables the menu on the NTP for accessing sessions from other devices.
 const char kDisableNTPOtherSessionsMenu[]   = "disable-ntp-other-sessions-menu";
 
@@ skipping 1090 matching lines @@
   if (base::CommandLine::ForCurrentProcess()->HasSwitch(kEnablePdfMaterialUI))
     return true;
 
   if (base::CommandLine::ForCurrentProcess()->HasSwitch(kDisablePdfMaterialUI))
     return false;
 
   // Default.
   return false;
 }
 
+bool MojoUtilityServicesEnabled() {

[jam, 2015/05/12 23:24:57]

we don't add methods for checking if one switch is enabled. just put this
directly in the three callers

[Anand Mistry (off Chromium), 2015/05/13 04:35:11]

The main reason I have this here is so that this can be disabled easily if a
regression is found in a release branch (and I can add an enable flag if
needed). The other reason is so that I can apply the same check (with same
ability to back out) to other utility process services I change.  Is that ok?

+  if (base::CommandLine::ForCurrentProcess()->HasSwitch(
+          kDisableMojoUtilityServices)) {
+    return false;
+  }
+
+  return true;
+}
+
 bool SettingsWindowEnabled() {
 #if defined(OS_CHROMEOS)
   return !base::CommandLine::ForCurrentProcess()->HasSwitch(
       ::switches::kDisableSettingsWindow);
 #else
   return base::CommandLine::ForCurrentProcess()->HasSwitch(
       ::switches::kEnableSettingsWindow);
 #endif
 }
 
 #if defined(OS_CHROMEOS)
 bool PowerOverlayEnabled() {
   return base::CommandLine::ForCurrentProcess()->HasSwitch(
       ::switches::kEnablePowerOverlay);
 }
 #endif
 
 // -----------------------------------------------------------------------------
 // DO NOT ADD YOUR CRAP TO THE BOTTOM OF THIS FILE.
 //
 // You were going to just dump your switches here, weren't you? Instead, please
 // put them in alphabetical order above, or in order inside the appropriate
 // ifdef at the bottom. The order should match the header.
 // -----------------------------------------------------------------------------
 
 }  // namespace switches