Clean up some lint complaints and fix center_of_mass()

src/core/SkPictureShader.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 "SkPictureShader.h"
 
 #include "SkBitmap.h"
@@ skipping 137 matching lines @@
     // The deserialization code won't trust that our serialized picture is safe to deserialize.
     // So write a 'false' telling it that we're not serializing a picture.
     if (buffer.isCrossProcess() && SkPicture::PictureIOSecurityPrecautionsEnabled()) {
         buffer.writeBool(false);
     } else {
         buffer.writeBool(true);
         fPicture->flatten(buffer);
     }
 }
 
-SkShader* SkPictureShader::refBitmapShader(const SkMatrix& matrix, const SkMatrix* localM,
-                                            const int maxTextureSize) const {
+SkShader* SkPictureShader::refBitmapShader(const SkMatrix& viewMatrix, const SkMatrix* localM,
+                                           const int maxTextureSize) const {
     SkASSERT(fPicture && !fPicture->cullRect().isEmpty());
 
     SkMatrix m;
-    m.setConcat(matrix, this->getLocalMatrix());
+    m.setConcat(viewMatrix, this->getLocalMatrix());
     if (localM) {
         m.preConcat(*localM);
     }
 
     // Use a rotation-invariant scale
     SkPoint scale;
     //
     // TODO: replace this with decomposeScale() -- but beware LayoutTest rebaselines!
     //
     if (!SkDecomposeUpper2x2(m, nullptr, &scale, nullptr)) {
@@ skipping 34 matching lines @@
 
     SkAutoTUnref<SkShader> tileShader;
     BitmapShaderKey key(fPicture->uniqueID(),
                         fTile,
                         fTmx,
                         fTmy,
                         tileScale,
                         this->getLocalMatrix());
 
     if (!SkResourceCache::Find(key, BitmapShaderRec::Visitor, &tileShader)) {
-        SkMatrix matrix;
-        matrix.setRectToRect(fTile, SkRect::MakeIWH(tileSize.width(), tileSize.height()),
+        SkMatrix tileMatrix;
+        tileMatrix.setRectToRect(fTile, SkRect::MakeIWH(tileSize.width(), tileSize.height()),
                              SkMatrix::kFill_ScaleToFit);
         SkBitmap bm;
         if (!SkInstallDiscardablePixelRef(
-            SkImageGenerator::NewFromPicture(tileSize, fPicture, &matrix, nullptr), &bm)) {
+            SkImageGenerator::NewFromPicture(tileSize, fPicture, &tileMatrix, nullptr), &bm)) {
             return nullptr;
         }
 
         SkMatrix shaderMatrix = this->getLocalMatrix();
         shaderMatrix.preScale(1 / tileScale.width(), 1 / tileScale.height());
         tileShader.reset(CreateBitmapShader(bm, fTmx, fTmy, &shaderMatrix));
 
         SkResourceCache::Add(new BitmapShaderRec(key, tileShader.get(), bm.getSize()));
     }
 
@@ skipping 90 matching lines @@
     if (context) {
         maxTextureSize = context->caps()->maxTextureSize();
     }
     SkAutoTUnref<SkShader> bitmapShader(this->refBitmapShader(viewM, localMatrix, maxTextureSize));
     if (!bitmapShader) {
         return nullptr;
     }
     return bitmapShader->asFragmentProcessor(context, viewM, nullptr, fq, procDataManager);
 }
 #endif