simplify bitmap scaler and cache

tests/SkResourceCacheTest.cpp

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "Test.h"
 #include "SkBitmapCache.h"
 #include "SkCanvas.h"
 #include "SkDiscardableMemoryPool.h"
 #include "SkGraphics.h"
 #include "SkResourceCache.h"
 #include "SkSurface.h"
 
 static const int kCanvasSize = 1;
 static const int kBitmapSize = 16;
 static const int kScale = 8;
 
 static bool is_in_scaled_image_cache(const SkBitmap& orig,
                                      SkScalar xScale,
                                      SkScalar yScale) {
     SkBitmap scaled;
-    float roundedImageWidth = SkScalarRoundToScalar(orig.width() * xScale);
-    float roundedImageHeight = SkScalarRoundToScalar(orig.height() * yScale);
-    return SkBitmapCache::Find(orig, roundedImageWidth, roundedImageHeight, &scaled);
+    int width = SkScalarRoundToInt(orig.width() * xScale);
+    int height = SkScalarRoundToInt(orig.height() * yScale);
+    return SkBitmapCache::FindWH(orig, width, height, &scaled);
 }
 
 // Draw a scaled bitmap, then return true if it has been cached.
 static bool test_scaled_image_cache_usage() {
     SkAutoTUnref<SkSurface> surface(SkSurface::NewRasterN32Premul(kCanvasSize, kCanvasSize));
     SkCanvas* canvas = surface->getCanvas();
     SkBitmap bitmap;
     bitmap.allocN32Pixels(kBitmapSize, kBitmapSize);
     bitmap.eraseColor(0xFFFFFFFF);
     SkScalar xScale = SkIntToScalar(kScale);
@@ skipping 242 matching lines @@
     cachedBitmap.unlockPixels();
 
     // We can add the bitmap back to the cache and find it again.
     REPORTER_ASSERT(reporter, SkBitmapCache::Add(cachedBitmap.pixelRef(), rect, cachedBitmap, cache));
     REPORTER_ASSERT(reporter, SkBitmapCache::Find(cachedBitmap.getGenerationID(), rect, &bm, cache));
 
     test_mipmapcache(reporter, cache);
     test_bitmap_notify(reporter, cache);
     test_mipmap_notify(reporter, cache);
 }