Fix wrap mode asserts in GrVkSampler::GenerateKey

Samplers now use their own enum rather than SkShader::TileMode.

Change-Id: I25324f7905a3c22fcd3699d6a0f778befa8c32da
Reviewed-on: https://skia-review.googlesource.com/49764
Commit-Queue: Brian Salomon <bsalomon@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
diff --git a/src/gpu/vk/GrVkSampler.cpp b/src/gpu/vk/GrVkSampler.cpp
index 822817b..d0ffcc1 100644
--- a/src/gpu/vk/GrVkSampler.cpp
+++ b/src/gpu/vk/GrVkSampler.cpp
@@ -82,12 +82,13 @@
     const int kTileModeYShift = 4;
     const int kMipLevelShift = 6;
 
+    SkASSERT(static_cast<int>(samplerState.filter()) <= 3);
     uint16_t key = static_cast<uint16_t>(samplerState.filter());
 
-    SkASSERT(static_cast<int>(samplerState.filter()) <= 3);
+    SkASSERT(static_cast<int>(samplerState.wrapModeX()) <= 4);
     key |= (static_cast<uint16_t>(samplerState.wrapModeX()) << kTileModeXShift);
 
-    GR_STATIC_ASSERT(SkShader::kTileModeCount <= 4);
+    SkASSERT(static_cast<int>(samplerState.wrapModeY()) <= 4);
     key |= (static_cast<uint16_t>(samplerState.wrapModeY()) << kTileModeYShift);
 
     SkASSERT(maxMipLevel < 1024);