Assert fDeviceClipBounds is always empty when clip is empty

I've fixed a few issues where this assert triggers.  The
nastiest case is when the client sets the clip to a strange
version of an empty rect (Ex: L,T,R,B=0,0,0,10).

I think I've made sufficient fixes so that
fDeviceClipBounds is always empty when clip is empty.

Let's test it though.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2246503003

Review-Url: https://codereview.chromium.org/2246503003
diff --git a/src/core/SkCanvas.cpp b/src/core/SkCanvas.cpp
index d199e5d..80ff34d 100644
--- a/src/core/SkCanvas.cpp
+++ b/src/core/SkCanvas.cpp
@@ -1863,7 +1863,7 @@
     // Verify that fDeviceClipBounds are set properly.
     SkRect tmp = qr_clip_bounds(fMCRec->fRasterClip.getBounds());
     if (fMCRec->fRasterClip.isEmpty()) {
-        SkASSERT(fDeviceClipBounds.isEmpty() || tmp == fDeviceClipBounds);
+        SkASSERT(fDeviceClipBounds.isEmpty());
     } else {
         SkASSERT(tmp == fDeviceClipBounds);
     }