Fix duplicate definition of kRect_ClipType.

kRect_ClipType is defined in GrTypesPriv.h and SkDevice.h. To fix this
change SkDevice::ClipType to be an enum class.

Bug: chromium:993871
Change-Id: I14b3f2b129a4e05414c23263a456b91bd2cb4175
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/234442
Reviewed-by: Florin Malita <fmalita@chromium.org>
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Florin Malita <fmalita@chromium.org>
diff --git a/src/core/SkCanvas.cpp b/src/core/SkCanvas.cpp
index fd6e093..1ab3867 100644
--- a/src/core/SkCanvas.cpp
+++ b/src/core/SkCanvas.cpp
@@ -1537,7 +1537,7 @@
 bool SkCanvas::isClipRect() const {
     SkBaseDevice* dev = this->getTopDevice();
     // if no device we return false
-    return dev && dev->onGetClipType() == SkBaseDevice::kRect_ClipType;
+    return dev && dev->onGetClipType() == SkBaseDevice::ClipType::kRect;
 }
 
 static inline bool is_nan_or_clipped(const Sk4f& devRect, const Sk4f& devClip) {
@@ -2991,5 +2991,3 @@
 }
 
 ///////////////////////////////////////////////////////////////////////////////////////////////////
-
-