refactor duplication (shouldSkip and skip_name) into a utility function

tools/flags/SkCommandLineFlags.h

Index: tools/flags/SkCommandLineFlags.h
diff --git a/tools/flags/SkCommandLineFlags.h b/tools/flags/SkCommandLineFlags.h
index d0e74502d8f98ce5eca8e474bb8db73dc3540878..51af9334677b2c2f2ba458d152a785a634e76835 100644
--- a/tools/flags/SkCommandLineFlags.h
+++ b/tools/flags/SkCommandLineFlags.h
@@ -10,6 +10,7 @@
 
 #include "SkString.h"
 #include "SkTArray.h"
+#include "SkTDArray.h"
 
 /**
  *  Including this file (and compiling SkCommandLineFlags.cpp) provides command line
@@ -90,7 +91,6 @@
  *  strings) so that a flag can be followed by multiple parameters.
  */
 
-
 class SkFlagInfo;
 
 class SkCommandLineFlags {
@@ -108,6 +108,15 @@ public:
      */
     static void Parse(int argc, char** argv);
 
+    /* Takes a list of the form [~][^]match[$]
+     ~ causes a matching test to always be skipped
+     ^ requires the start of the test to match
+     $ requires the end of the test to match
+     ^ and $ requires an exact match
+     If a test does not match any list entry, it is skipped unless some list entry starts with ~
+    */
+    static bool ShouldSkip(const SkTDArray<const char*>& strings, const char* name);
+
     /**
      *  Custom class for holding the arguments for a string flag.
      *  Publicly only has accessors so the strings cannot be modified.