Vulkan: Fix missing xfb buffer rebind on new command buffer

When a command buffer is ended, bindings are lost.  This adds a dirty
bit to `mNewGraphicsCommandBufferDirtyBits` to make sure transform
feedback buffers are bound again on the new command buffer.

Bug: angleproject:5428
Change-Id: I7733c93b1eb5d33a77cbee231a83199be950e19f
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2611552
Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>

src/libANGLE/renderer/vulkan/ContextVk.cpp

@@ -416,6 +416,13 @@ ContextVk::ContextVk(const gl::State &state, gl::ErrorSet *errorSet, RendererVk
 
     mIndexedDirtyBitsMask.set();
 
+    // Once a command buffer is ended, all bindings (through |vkCmdBind*| calls) are lost per Vulkan
+    // spec.  Once a new command buffer is allocated, we must make sure every previously bound
+    // resource is bound again.
+    //
+    // Note that currently these dirty bits are set every time a new render pass command buffer is
+    // begun.  However, using ANGLE's SecondaryCommandBuffer, the Vulkan command buffer (which is
+    // the primary command buffer) is not ended, so technically we don't need to rebind these.
     mNewGraphicsCommandBufferDirtyBits.set(DIRTY_BIT_PIPELINE);
     mNewGraphicsCommandBufferDirtyBits.set(DIRTY_BIT_TEXTURES);
     mNewGraphicsCommandBufferDirtyBits.set(DIRTY_BIT_VERTEX_BUFFERS);
@@ -423,6 +430,10 @@ ContextVk::ContextVk(const gl::State &state, gl::ErrorSet *errorSet, RendererVk
     mNewGraphicsCommandBufferDirtyBits.set(DIRTY_BIT_SHADER_RESOURCES);
     mNewGraphicsCommandBufferDirtyBits.set(DIRTY_BIT_DESCRIPTOR_SETS);
     mNewGraphicsCommandBufferDirtyBits.set(DIRTY_BIT_DRIVER_UNIFORMS_BINDING);
+    if (getFeatures().supportsTransformFeedbackExtension.enabled)
+    {
+        mNewGraphicsCommandBufferDirtyBits.set(DIRTY_BIT_TRANSFORM_FEEDBACK_BUFFERS);
+    }
 
     mNewComputeCommandBufferDirtyBits.set(DIRTY_BIT_PIPELINE);
     mNewComputeCommandBufferDirtyBits.set(DIRTY_BIT_TEXTURES);

src/tests/gl_tests/TransformFeedbackTest.cpp

@@ -289,9 +289,6 @@ TEST_P(TransformFeedbackTest, SpanMultipleRenderPasses)
     // Fails on Mac GL drivers. http://anglebug.com/4992
     ANGLE_SKIP_TEST_IF(IsOpenGL() && IsOSX());
 
-    // anglebug.com/5428
-    ANGLE_SKIP_TEST_IF(IsLinux() && IsIntel() && IsVulkan());
-
     // anglebug.com/5429
     ANGLE_SKIP_TEST_IF(IsAndroid() && IsOpenGLES());