name parameters for docs

SkPixmap.h is missing a couple
of parameter names. Named parameters
helps bookmaker generate markdown
and doxygen that describe methods
and functions.

TBR=reed@google.com
Bug: skia:6898
Change-Id: I8f9e1acd677e57e71c26c34759ce4647a5db0548
Reviewed-on: https://skia-review.googlesource.com/42380
Commit-Queue: Cary Clark <caryclark@skia.org>
Reviewed-by: Cary Clark <caryclark@skia.org>
diff --git a/include/core/SkPixmap.h b/include/core/SkPixmap.h
index 55e38cc..2f036e8 100644
--- a/include/core/SkPixmap.h
+++ b/include/core/SkPixmap.h
@@ -36,13 +36,13 @@
     }
 
     // overrides the colorspace in the SkImageInfo of the pixmap
-    void setColorSpace(sk_sp<SkColorSpace>);
+    void setColorSpace(sk_sp<SkColorSpace> colorSpace);
 
     /**
      *  If supported, set this pixmap to point to the pixels in the specified mask and return true.
      *  On failure, return false and set this pixmap to empty.
      */
-    bool SK_WARN_UNUSED_RESULT reset(const SkMask&);
+    bool SK_WARN_UNUSED_RESULT reset(const SkMask& mask);
 
     /**
      *  Computes the intersection of area and this pixmap. If that intersection is non-empty,
@@ -205,7 +205,7 @@
     bool erase(SkColor, const SkIRect& subset) const;
 
     bool erase(SkColor color) const { return this->erase(color, this->bounds()); }
-    bool erase(const SkColor4f&, const SkIRect* subset = nullptr) const;
+    bool erase(const SkColor4f& color, const SkIRect* subset = nullptr) const;
 
 private:
     const void*     fPixels;