Revert of remove (dumb) canvas::NewRaster, and rename surface::NewRasterPMColor to N32Premul (patchset #3 id:40001 of https://codereview.chromium.org/790733003/)

Reason for revert:
need to update chrome first

Original issue's description:
> remove (dumb) canvas::NewRaster, and rename surface::NewRasterPMColor to N32Premul
>
> patch from issue 781403002 at patchset 20001 (http://crrev.com/781403002#ps20001)
>
> BUG=skia:
>
> Committed: https://skia.googlesource.com/skia/+/2c1605a1fbaa2e35a27399a34254fb1200ec2ae6

TBR=fmalita@google.com,fmalita@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=skia:

Review URL: https://codereview.chromium.org/791763002

2 files changed, 29 insertions, 5 deletions

diff --git a/include/core/SkCanvas.h b/include/core/SkCanvas.h
index 46dc3774f0..ff60c57fa7 100644
--- a/include/core/SkCanvas.h
+++ b/include/core/SkCanvas.h
@@ -62,6 +62,35 @@ public:
     SK_DECLARE_INST_COUNT(SkCanvas)
 
     /**
+     *  Attempt to allocate an offscreen raster canvas, matching the ImageInfo.
+     *  On success, return a new canvas that will draw into that offscreen.
+     *
+     *  The caller can access the pixels after drawing into this canvas by
+     *  calling readPixels() or peekPixels().
+     *
+     *  If the requested ImageInfo is opaque (either the colortype is
+     *  intrinsically opaque like RGB_565, or the info's alphatype is kOpaque)
+     *  then the pixel memory may be uninitialized. Otherwise, the pixel memory
+     *  will be initialized to 0, which is interpreted as transparent.
+     *
+     *  On failure, return NULL. This can fail for several reasons:
+     *  1. the memory allocation failed (e.g. request is too large)
+     *  2. invalid ImageInfo (e.g. negative dimensions)
+     *  3. unsupported ImageInfo for a canvas
+     *      - kUnknown_SkColorType, kIndex_8_SkColorType
+     *      - kIgnore_SkAlphaType
+     *      - this list is not complete, so others may also be unsupported
+     *
+     *  Note: it is valid to request a supported ImageInfo, but with zero
+     *  dimensions.
+     */
+    static SkCanvas* NewRaster(const SkImageInfo&);
+
+    static SkCanvas* NewRasterN32(int width, int height) {
+        return NewRaster(SkImageInfo::MakeN32Premul(width, height));
+    }
+
+    /**
      *  Attempt to allocate raster canvas, matching the ImageInfo, that will draw directly into the
      *  specified pixels. To access the pixels after drawing to them, the caller should call
      *  flush() or call peekPixels(...).
diff --git a/include/core/SkSurface.h b/include/core/SkSurface.h
index 7563d09842..0e238f8429 100644
--- a/include/core/SkSurface.h
+++ b/include/core/SkSurface.h
@@ -61,14 +61,9 @@ public:
      *  specified width and height, and populates the rest of info to match
      *  pixels in SkPMColor format.
      */
-#ifdef SK_SUPPORT_LEGACY_NewRasterPMColor
     static SkSurface* NewRasterPMColor(int width, int height, const SkSurfaceProps* props = NULL) {
         return NewRaster(SkImageInfo::MakeN32Premul(width, height), props);
     }
-#endif
-    static SkSurface* NewRasterN32Premul(int width, int height, const SkSurfaceProps* props = NULL) {
-        return NewRaster(SkImageInfo::MakeN32Premul(width, height), props);
-    }
 
     /**
      *  Return a new surface using the specified render target.