title: Android Gradle Project upgrading build tools to 21.0.1: aapt throws Exception
body: <p>We have an android gradle project. Today I wanted to upgrade the android build tools version from 20 to 21.0.1, but now the aapt is failing.</p>
  
  <pre><code>* What went wrong:
  Execution failed for task ':myproject-android:processDebugResources'.
  &gt; com.android.ide.common.internal.LoggedErrorException: Failed to run command:
          c:\_DEVELOP\AndroidSDK\sdk\build-tools\21.0.1\aapt.exe package -f --no-crunch -I c:\_DEVELOP\AndroidSDK\sdk\platforms\android-16\android.jar -M D:\_MY_PROJECT\trunk\myproject_bin\gradle\build\re
  lease\myproject-android\intermediates\manifests\full\debug\AndroidManifest.xml -S D:\_MY_PROJECT\trunk\myproject_bin\gradle\build\release\myproject-android\intermediates\res\debug -A D:\_MY_PROJECT\tr
  unk\myproject_bin\gradle\build\release\myproject-android\intermediates\assets\debug -m -J D:\_MY_PROJECT\trunk\myproject_bin\gradle\build\release\myproject-android\generated\source\r\debug -F D:\_PIVOSC
  ORE_P4\trunk\myproject_bin\gradle\build\release\myproject-android\intermediates\res\resources-debug.ap_ --debug-mode --custom-package com.myproject.app -0 apk --output-text-symbols D:\_MY_PROJECT\trunk\
  myproject_bin\gradle\build\release\myproject-android\intermediates\symbols\debug
  Error Code:
          255
  </code></pre>
  
  <p>I had some warnings saying:</p>
  
  <pre><code>libpng warning: iCCP: Not recognizing known sRGB profile that has been edited
  </code></pre>
  
  <p>I fixed those, but there are 6 more in the appcompat-v7 library.</p>
  
  <p>If I revert the build tools version to 20 everything works fine.</p>
  
  <p>Has anyone came across this problem?</p>