Revert "Fix signed/unsigned comparison in assert"

This reverts commit ed6d6daa566c2576cd41b94b6d856d27ae325274.

Reason for revert: vulkan crash

Original change's description:
> Fix signed/unsigned comparison in assert
> 
> Bug: skia:
> Change-Id: I4759ea1c42cad1d1b1f159d1d8c2c607453abad7
> Reviewed-on: https://skia-review.googlesource.com/66900
> Reviewed-by: Jim Van Verth <jvanverth@google.com>
> Commit-Queue: Chris Dalton <csmartdalton@google.com>

TBR=jvanverth@google.com,csmartdalton@google.com

Change-Id: Idedaf001ba86bf76b86c317bbfeaf4226e37d314
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: skia:
Reviewed-on: https://skia-review.googlesource.com/67020
Reviewed-by: Jim Van Verth <jvanverth@google.com>
diff --git a/src/gpu/vk/GrVkCommandBuffer.cpp b/src/gpu/vk/GrVkCommandBuffer.cpp
index 0796722..ba19168 100644
--- a/src/gpu/vk/GrVkCommandBuffer.cpp
+++ b/src/gpu/vk/GrVkCommandBuffer.cpp
@@ -333,8 +333,7 @@
                                              uint32_t discardRectangleCount,
                                              const VkRect2D* discardRectangles) {
     SkASSERT(fIsActive);
-    SkASSERT(firstDiscardRectangle + discardRectangleCount <=
-             (uint32_t)gpu->vkCaps().maxWindowRectangles());
+    SkASSERT(firstDiscardRectangle + discardRectangleCount <= gpu->vkCaps().maxWindowRectangles());
     SkASSERT(gpu->vkCaps().maxWindowRectangles() <= GrWindowRectangles::kMaxWindows);
     if (memcmp(discardRectangles, &fCachedDiscardRectangles[firstDiscardRectangle],
                discardRectangleCount * sizeof(VkRect2D))) {