Remove unused matrix param from GrContext/GrDrawTarget rect drawing functions.

R=robertphillips@google.com

Author: bsalomon@google.com

Review URL: https://codereview.chromium.org/441623005
diff --git a/src/gpu/GrClipMaskManager.cpp b/src/gpu/GrClipMaskManager.cpp
index 704750e..edd4454 100644
--- a/src/gpu/GrClipMaskManager.cpp
+++ b/src/gpu/GrClipMaskManager.cpp
@@ -407,7 +407,7 @@
                                                               element->getRect(),
                                                               false);
             } else {
-                fGpu->drawSimpleRect(element->getRect(), NULL);
+                fGpu->drawSimpleRect(element->getRect());
             }
             return true;
         default: {
@@ -481,7 +481,7 @@
                                       GrTextureDomain::MakeTexelDomain(srcMask, srcBound),
                                       GrTextureDomain::kDecal_Mode,
                                       GrTextureParams::kNone_FilterMode))->unref();
-    fGpu->drawSimpleRect(SkRect::Make(dstBound), NULL);
+    fGpu->drawSimpleRect(SkRect::Make(dstBound));
 }
 
 // get a texture to act as a temporary buffer for AA clip boolean operations
@@ -812,7 +812,7 @@
                 SET_RANDOM_COLOR
                 if (Element::kRect_Type == element->getType()) {
                     *drawState->stencil() = gDrawToStencil;
-                    fGpu->drawSimpleRect(element->getRect(), NULL);
+                    fGpu->drawSimpleRect(element->getRect());
                 } else {
                     if (!clipPath.isEmpty()) {
                         if (canRenderDirectToStencil) {
@@ -833,7 +833,7 @@
                 if (canDrawDirectToClip) {
                     if (Element::kRect_Type == element->getType()) {
                         SET_RANDOM_COLOR
-                        fGpu->drawSimpleRect(element->getRect(), NULL);
+                        fGpu->drawSimpleRect(element->getRect());
                     } else {
                         SET_RANDOM_COLOR
                         pr->drawPath(clipPath, stroke, fGpu, false);
@@ -842,7 +842,7 @@
                     SET_RANDOM_COLOR
                     // The view matrix is setup to do clip space -> stencil space translation, so
                     // draw rect in clip space.
-                    fGpu->drawSimpleRect(SkRect::Make(clipSpaceIBounds), NULL);
+                    fGpu->drawSimpleRect(SkRect::Make(clipSpaceIBounds));
                 }
             }
         }