Fix string assert and dead code which caused it.

tools/flags/SkCommandLineFlags.cpp

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkCommandLineFlags.h"
 #include "SkTDArray.h"
 
@@ skipping 269 matching lines @@
                             flag->setDouble(atof(argv[i]));
                             break;
                         default:
                             SkDEBUGFAIL("Invalid flag type");
                     }
                     break;
                 }
                 flag = flag->next();
             }
             if (!flagMatched) {
-                SkString stripped(argv[i]);
-                while (stripped.startsWith('-')) {
-                    stripped.remove(0, 1);
-                }
                 if (!FLAGS_undefok) {
                     SkDebugf("Got unknown flag \"%s\". Exiting.\n", argv[i]);
                     exit(-1);
                 }
             }
         }
     }
     // Since all of the flags have been set, release the memory used by each
     // flag. FLAGS_x can still be used after this.
     SkFlagInfo* flag = gHead;
@@ skipping 43 matching lines @@
 }
 
 }  // namespace
 
 bool SkCommandLineFlags::ShouldSkip(const SkTDArray<const char*>& strings, const char* name) {
     return ShouldSkipImpl(strings, name);
 }
 bool SkCommandLineFlags::ShouldSkip(const StringArray& strings, const char* name) {
     return ShouldSkipImpl(strings, name);
 }