adding preabandon flag to DM

tools/flags/SkCommonFlags.cpp

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkCommonFlags.h"
 
 DEFINE_string(config, "565 8888 gpu nonrendering angle nvprmsaa4 hwui ",
@@ skipping 21 matching lines @@
                "Multiple matches may be separated by spaces.\n"
                "~ causes a matching GM to always be skipped\n"
                "^ requires the start of the GM to match\n"
                "$ requires the end of the GM to match\n"
                "^ and $ requires an exact match\n"
                "If a GM does not match any list entry,\n"
                "it is skipped unless some list entry starts with ~");
 
 DEFINE_bool2(quiet, q, false, "if true, don't print status updates.");
 
+DEFINE_bool(preAbandonGpuContext, false, "Abandons the GrContext before running the test.");
+
 DEFINE_bool(abandonGpuContext, false, "Abandon the GrContext after running each test.");
 
 DEFINE_string(skps, "skps", "Directory to read skps from.");
 
 DEFINE_int32(threads, -1, "Run threadsafe tests on a threadpool with this many extra threads, "
                           "defaulting to one extra thread per core.");
 
 DEFINE_bool2(verbose, v, false, "enable verbose output from the test driver.");
 
 DEFINE_bool2(veryVerbose, V, false, "tell individual tests to be verbose.");
 
 DEFINE_string2(writePath, w, "", "If set, write bitmaps here as .pngs.");
 
 DEFINE_string(key, "",
               "Space-separated key/value pairs to add to JSON identifying this builder.");
 DEFINE_string(properties, "",
               "Space-separated key/value pairs to add to JSON identifying this run.");