Remove asserts on scissor size in Vulkan

src/gpu/vk/GrVkPipeline.cpp

 /*
 * Copyright 2016 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */
 
 #include "GrVkPipeline.h"
 
 #include "GrGeometryProcessor.h"
@@ skipping 477 matching lines @@
                                GrVkCommandBuffer* cmdBuffer,
                                const GrPipeline& pipeline,
                                const GrRenderTarget& target) {
     // We always use one scissor and if it is disabled we just make it the size of the RT
     const GrScissorState& scissorState = pipeline.getScissorState();
     VkRect2D scissor;
     if (scissorState.enabled() &&
         !scissorState.rect().contains(0, 0, target.width(), target.height())) {
         // This all assumes the scissorState has previously been clipped to the device space render
         // target.
-        scissor.offset.x = scissorState.rect().fLeft;
+        scissor.offset.x = SkTMax(scissorState.rect().fLeft, 0);
         scissor.extent.width = scissorState.rect().width();
         if (kTopLeft_GrSurfaceOrigin == target.origin()) {
             scissor.offset.y = scissorState.rect().fTop;
         } else {
             SkASSERT(kBottomLeft_GrSurfaceOrigin == target.origin());
             scissor.offset.y = target.height() - scissorState.rect().fBottom;
         }
+        scissor.offset.y = SkTMax(scissor.offset.y, 0);
         scissor.extent.height = scissorState.rect().height();
 
         SkASSERT(scissor.offset.x >= 0);
-        SkASSERT(scissor.offset.x + scissor.extent.width <= (uint32_t)target.width());
         SkASSERT(scissor.offset.y >= 0);
-        SkASSERT(scissor.offset.y + scissor.extent.height <= (uint32_t)target.height());
     } else {
         scissor.extent.width = target.width();
         scissor.extent.height = target.height();
         scissor.offset.x = 0;
         scissor.offset.y = 0;
     }
     cmdBuffer->setScissor(gpu, 0, 1, &scissor);
 }
 
 void set_dynamic_viewport_state(GrVkGpu* gpu,
@@ skipping 27 matching lines @@
 }
 
 void GrVkPipeline::SetDynamicState(GrVkGpu* gpu,
                                    GrVkCommandBuffer* cmdBuffer,
                                    const GrPipeline& pipeline) {
     const GrRenderTarget& target = *pipeline.getRenderTarget();
     set_dynamic_scissor_state(gpu, cmdBuffer, pipeline, target);
     set_dynamic_viewport_state(gpu, cmdBuffer, target);
     set_dynamic_blend_constant_state(gpu, cmdBuffer, pipeline);
 }