replace setConfig+allocPixels with single call

BUG=skia:

Review URL: https://codereview.chromium.org/162643002

git-svn-id: http://skia.googlecode.com/svn/trunk@13426 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/tests/SkpSkGrTest.cpp b/tests/SkpSkGrTest.cpp
index 2c01a7e..02aabbe 100644
--- a/tests/SkpSkGrTest.cpp
+++ b/tests/SkpSkGrTest.cpp
@@ -425,8 +425,7 @@
         do {
             dim.fX = (pWidth + scale - 1) / scale;
             dim.fY = (pHeight + scale - 1) / scale;
-            bitmap.setConfig(SkBitmap::kARGB_8888_Config, dim.fX, dim.fY);
-            bool success = bitmap.allocPixels();
+            bool success = bitmap.allocN32Pixels(, dim.fX, dim.fY);
             if (success) {
                 break;
             }