[SkTextBlob] Merge run font data at draw time.

src/core/SkCanvas.cpp

 /*
  * Copyright 2008 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #include "SkCanvas.h"
 #include "SkCanvasPriv.h"
@@ skipping 2208 matching lines @@
 void SkCanvas::onDrawTextBlob(const SkTextBlob* blob, SkScalar x, SkScalar y,
                               const SkPaint& paint) {
     SkASSERT(blob);
 
     // FIXME: dispatch to the device instead
 
     if (x || y) {
         this->translate(x, y);
     }
 
+    SkPaint runPaint = paint;
     SkTextBlob::RunIterator it(blob);
     while (!it.done()) {
         size_t textLen = it.glyphCount() * sizeof(uint16_t);
         const SkPoint& offset = it.offset();
+        // applyFontToPaint() always overwrites the exact same attributes,
+        // so it is safe to not re-seed the paint.
+        it.applyFontToPaint(&runPaint);
 
         switch (it.positioning()) {
         case SkTextBlob::kDefault_Positioning:
-            this->drawText(it.glyphs(), textLen, offset.x(), offset.y(), paint);
+            this->drawText(it.glyphs(), textLen, offset.x(), offset.y(), runPaint);
             break;
         case SkTextBlob::kHorizontal_Positioning:
-            this->drawPosTextH(it.glyphs(), textLen, it.pos(), offset.y(), paint);
+            this->drawPosTextH(it.glyphs(), textLen, it.pos(), offset.y(), runPaint);
             break;
         case SkTextBlob::kFull_Positioning:
-            this->drawPosText(it.glyphs(), textLen, (const SkPoint*)it.pos(), paint);
+            this->drawPosText(it.glyphs(), textLen, (const SkPoint*)it.pos(), runPaint);
             break;
         default:
             SkFAIL("unhandled positioning mode");
         }
 
         it.next();
     }
 
     if (x || y) {
         this->translate(-x, -y);
@@ skipping 337 matching lines @@
     }
 
     if (NULL != matrix) {
         canvas->concat(*matrix);
     }
 }
 
 SkAutoCanvasMatrixPaint::~SkAutoCanvasMatrixPaint() {
     fCanvas->restoreToCount(fSaveCount);
 }