Add json output to Junit tests.

testing/android/junit/java/src/org/chromium/testing/local/JunitTestArgParser.java

 // 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.
 
 package org.chromium.testing.local;
 
+import java.io.File;
 import java.util.HashSet;
 import java.util.Set;
 
 /**
  *  Parses command line arguments for JunitTestMain.
  */
 public class JunitTestArgParser {
 
     private final Set<String> mPackageFilters;
     private final Set<Class<?>> mRunnerFilters;
     private final Set<String> mGtestFilters;
+    private File mJsonOutput;
 
     public static JunitTestArgParser parse(String[] args) {
 
         JunitTestArgParser parsed = new JunitTestArgParser();
 
         for (int i = 0; i < args.length; ++i) {
             if (args[i].startsWith("-")) {
                 String argName;
                 if (args[i].startsWith("-", 1)) {
                     argName = args[i].substring(2, args[i].length());
                 } else {
                     argName = args[i].substring(1, args[i].length());
                 }
                 try {
                     if ("package-filter".equals(argName)) {
                         // Read the command line argument after the flag.
                         parsed.addPackageFilter(args[++i]);
                     } else if ("runner-filter".equals(argName)) {
                         // Read the command line argument after the flag.
                         parsed.addRunnerFilter(Class.forName(args[++i]));
                     } else if ("gtest-filter".equals(argName)) {
                         // Read the command line argument after the flag.
                         parsed.addGtestFilter(args[++i]);
+                    } else if ("json-results-file".equals(argName)) {
+                        // Read the command line argument after the flag.
+                        parsed.setJsonOutputFile(args[++i]);
                     } else {
                         System.out.println("Ignoring flag: \"" + argName + "\"");
                     }
                 } catch (ArrayIndexOutOfBoundsException e) {
                     System.err.println("No value specified for argument \"" + argName + "\"");
                     System.exit(1);
                 } catch (ClassNotFoundException e) {
                     System.err.println("Class not found. (" + e.toString() + ")");
                     System.exit(1);
                 }
             } else {
                 System.out.println("Ignoring argument: \"" + args[i] + "\"");
             }
         }
 
         return parsed;
     }
 
     private JunitTestArgParser() {
         mPackageFilters = new HashSet<String>();
         mRunnerFilters = new HashSet<Class<?>>();
         mGtestFilters = new HashSet<String>();
+        mJsonOutput = null;
     }
 
     public Set<String> getPackageFilters() {
         return mPackageFilters;
     }
 
     public Set<Class<?>> getRunnerFilters() {
         return mRunnerFilters;
     }
 
     public Set<String> getGtestFilters() {
         return mGtestFilters;
     }
 
+    public File getJsonOutputFile() {
+        return mJsonOutput;
+    }
+
     private void addPackageFilter(String packageFilter) {
         mPackageFilters.add(packageFilter);
     }
 
     private void addRunnerFilter(Class<?> runnerFilter) {
         mRunnerFilters.add(runnerFilter);
     }
 
     private void addGtestFilter(String gtestFilter) {
         mGtestFilters.add(gtestFilter);
     }
 
+    private void setJsonOutputFile(String path) {
+        mJsonOutput = new File(path);
+    }
+
 }