Allocate only the vertices we need for text.

src/gpu/GrTextContext.cpp

 /*
  * Copyright 2010 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrTextContext.h"
 #include "GrContext.h"
 
@@ skipping 58 matching lines @@
             return true;
         }
         textContext = textContext->fFallbackTextContext;
     } while (textContext);
 
     return false;
 }
 
 
 //*** change to output positions?
-void GrTextContext::MeasureText(SkGlyphCache* cache, SkDrawCacheProc glyphCacheProc,
+int GrTextContext::MeasureText(SkGlyphCache* cache, SkDrawCacheProc glyphCacheProc,
                                 const char text[], size_t byteLength, SkVector* stopVector) {
     SkFixed     x = 0, y = 0;
     const char* stop = text + byteLength;
 
     SkAutoKern  autokern;
 
+    int numGlyphs = 0;
     while (text < stop) {
         // don't need x, y here, since all subpixel variants will have the
         // same advance
         const SkGlyph& glyph = glyphCacheProc(cache, &text, 0, 0);
 
         x += autokern.adjust(glyph) + glyph.fAdvanceX;
         y += glyph.fAdvanceY;
+        ++numGlyphs;
     }
     stopVector->set(SkFixedToScalar(x), SkFixedToScalar(y));
 
     SkASSERT(text == stop);
+    
+    return numGlyphs;
 }
 
 static void GlyphCacheAuxProc(void* data) {
     GrFontScaler* scaler = (GrFontScaler*)data;
     SkSafeUnref(scaler);
 }
 
 GrFontScaler* GrTextContext::GetGrFontScaler(SkGlyphCache* cache) {
     void* auxData;
     GrFontScaler* scaler = NULL;
 
     if (cache->getAuxProcData(GlyphCacheAuxProc, &auxData)) {
         scaler = (GrFontScaler*)auxData;
     }
     if (NULL == scaler) {
         scaler = SkNEW_ARGS(GrFontScaler, (cache));
         cache->setAuxProc(GlyphCacheAuxProc, scaler);
     }
 
     return scaler;
 }