Revert of SkCanvas::clear() should call down to devices even when the clip is empty. (patchset #1 id:1 of https://codereview.chromium.org/735233003/)

Reason for revert:
Chrome unit_tests failures on Mac & Win, blocking the roll: http://build.chromium.org/p/tryserver.chromium.win/builders/win_chromium_rel_ng/builds/5613

Original issue's description:
> SkCanvas::clear() should call down to devices even when the clip is empty.
>
> SkDrawIter had a lovely, completely unused, option for this.  Oversight?
>
> BUG=skia:
>
> Committed: https://skia.googlesource.com/skia/+/378e70d8e561b72a904286ea231946f5c8345b9a

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

Review URL: https://codereview.chromium.org/748733002

src/core/SkCanvas.cpp

@@ -1707,7 +1707,7 @@ void SkCanvas::drawDRRect(const SkRRect& outer, const SkRRect& inner,
 //////////////////////////////////////////////////////////////////////////////
 
 void SkCanvas::clear(SkColor color) {
-    SkDrawIter  iter(this, false/*clear can affect empty clips*/);
+    SkDrawIter  iter(this);
     this->predrawNotify();
     while (iter.next()) {
         iter.fDevice->clear(color);

tests/CanvasTest.cpp

@@ -795,17 +795,3 @@ DEF_TEST(Canvas, reporter) {
 
     test_newraster(reporter);
 }
-
-// Make sure SkCanvas passes clear() calls down to its devices even when they're clipped out.
-DEF_TEST(Canvas_clear, reporter) {
-    SkBitmap bm;
-    bm.allocN32Pixels(1,1);
-
-    SkCanvas canvas(bm);
-    canvas.clear(SK_ColorRED);
-    REPORTER_ASSERT(reporter, SK_ColorRED == bm.getColor(0,0));
-
-    canvas.clipRect(SkRect::MakeEmpty());
-    canvas.clear(SK_ColorGREEN);
-    REPORTER_ASSERT(reporter, SK_ColorGREEN == bm.getColor(0,0));
-}