Roll Android SDK to v21

build/config/android/config.gni

 # Copyright 2014 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.
 
 # This file contains common system config stuff for the Android build.
 
 if (is_android) {
   declare_args() {
     # Absolute directory containing the Android source code.
     android_src = ""
 
     android_sdk_root = "//third_party/android_tools/sdk"
-    android_sdk_version = "20"
+    android_sdk_version = "21"
 
     # This is set when building the Android WebView inside the Android build
     # system, using the 'android' gyp backend. The WebView code is still built
     # when this is unset, but builds using the normal chromium build system.
     is_android_webview_build = false
 
     android_default_keystore_path = "//build/android/ant/chromium-debug.keystore"
     android_default_keystore_name = "chromiumdebugkey"
     android_default_keystore_password = "chromium"
 
@@ skipping 37 matching lines @@
 
   android_sdk = "${android_sdk_root}/platforms/android-${android_sdk_version}"
 
   # Path to the Android NDK and SDK.
   android_ndk_root = "//third_party/android_tools/ndk"
   android_ndk_include_dir = "$android_ndk_root/usr/include"
 
   android_sdk = "${android_sdk_root}/platforms/android-${android_sdk_version}"
 
   android_sdk_tools = "${android_sdk_root}/tools"
-  android_sdk_build_tools = "${android_sdk_root}/build-tools/20.0.0"
+  android_sdk_build_tools = "${android_sdk_root}/build-tools/21.0.0"
 
   # Path to the SDK's android.jar
   android_sdk_jar = "$android_sdk/android.jar"
 
   zipalign_path = "$android_sdk_build_tools/zipalign"
 
   # Subdirectories inside android_ndk_root that contain the sysroot for the
   # associated platform.
   _android_api_level = 14
   x86_android_sysroot_subdir = "platforms/android-${_android_api_level}/arch-x86"
@@ skipping 62 matching lines @@
     android_app_abi = "mips"
   } else {
     assert(false, "Unknown Android ABI: " + cpu_arch)
   }
 } else {
   if (!defined(is_android_webview_build)) {
     is_android_webview_build = false
   }
   use_system_stlport = false
 }