Update Android build to API level 17 and SDK Tools version 21

build/android/ant/create-test-jar.js

 // 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.
 
 /**
  * Combines classes from javac.custom.classpath property and ${out.dir}/classes
  * into a single jar file ${ant.project.name}.jar and places the file in
  * ${lib.java.dir}.
  */
 
 importClass(java.io.File);
 importClass(org.apache.tools.ant.types.Reference);
 importClass(org.apache.tools.ant.types.FileSet);
 importClass(org.apache.tools.ant.types.ZipFileSet);
 importClass(org.apache.tools.ant.taskdefs.Zip);
 
-var echo = project.createTask("echo");
 var jarTask = project.createTask("jar");
 
 // Do not allow duplicates in the jar, the default behavior of Jar task
 // is "add" which means duplicates are allowed.
 // This can cause a class file to be included multiple times, setting the
 // duplicate to "preserve" ensures that only the first definition is included.
 
 var duplicate = Zip.Duplicate();
 duplicate.setValue("preserve");
 jarTask.setDuplicate(duplicate);
@@ skipping 29 matching lines @@
     (project.getProperty("project.app.package")).replace('.','/');
 var excludedClasses = ["R.class", "R$*.class", "Manifest.class",
     "Manifest$*.class", "BuildConfig.class"]
 
 var exclusionString = "";
 for (var i in excludedClasses) {
   exclusionString += appPackagePath+ "/" + excludedClasses[i] + " ";
 }
 
 jarTask.setExcludes(exclusionString);
-echo.setMessage("Creating test jar: " +
-                jarTask.getDestFile().getAbsolutePath());
-echo.perform();
 jarTask.perform();