Fix size_t to int conversion warning on Win64 in SkRTConf.h.

include/utils/SkRTConf.h

 /*
  * Copyright 2013 Google, Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #ifndef SkRTConf_DEFINED
 #define SkRTConf_DEFINED
@@ skipping 97 matching lines @@
     skRTConfRegistry().registerConf(this);
 }
 
 template<typename T>
 void SkRTConf<T>::print(SkWStream *o) const {
     char outline[200]; // should be ok because we specify a max. width for everything here.
 
     sprintf(outline, "%-30.30s", getName());
     doPrint(&(outline[30]));
     sprintf(&(outline[60]), " %.128s", fDescription.c_str());
-    if (' ' == outline[strlen(outline)-1]) {
-        for (int i = strlen(outline)-1 ; ' ' == outline[i] ; i--) {
-            outline[i] = '\0';
-        }
+    for (size_t i = strlen(outline); i --> 0 && ' ' == outline[i];) {
+        outline[i] = '\0';
     }
     o->writeText(outline);
 }
 
 template<typename T>
 void SkRTConf<T>::doPrint(char *s) const {
     sprintf(s, "%-30.30s", "How do I print myself??");
 }
 
 template<> inline void SkRTConf<bool>::doPrint(char *s) const {
@@ skipping 37 matching lines @@
     // static_cast here is okay because there's only one kind of child class.
     const SkRTConf<T> *child_pointer = static_cast<const SkRTConf<T> *>(conf);
     return child_pointer &&
            fName == child_pointer->fName &&
            fDescription == child_pointer->fDescription &&
            fValue == child_pointer->fValue &&
            fDefault == child_pointer->fDefault;
 }
 
 #endif