Combine GPU flush with semaphore API

Bug: skia:
Change-Id: I5f388760d43b19755b2767d95d32065f6d0f926e
Reviewed-on: https://skia-review.googlesource.com/14646
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
diff --git a/src/gpu/vk/GrVkGpu.cpp b/src/gpu/vk/GrVkGpu.cpp
index 66dbf42..a107ee2 100644
--- a/src/gpu/vk/GrVkGpu.cpp
+++ b/src/gpu/vk/GrVkGpu.cpp
@@ -1924,9 +1924,10 @@
     return GrVkSemaphore::Make(this);
 }
 
-void GrVkGpu::insertSemaphore(sk_sp<GrSemaphore> semaphore) {
+void GrVkGpu::insertSemaphore(sk_sp<GrSemaphore> semaphore, bool /*flush*/) {
     GrVkSemaphore* vkSem = static_cast<GrVkSemaphore*>(semaphore.get());
 
+    // We *always* flush, so ignore that parameter
     this->submitCommandBuffer(kSkip_SyncQueue, vkSem->getResource());
 }
 
@@ -1937,7 +1938,3 @@
     resource->ref();
     fSemaphoresToWaitOn.push_back(resource);
 }
-
-void GrVkGpu::flush() {
-    // We submit the command buffer to the queue whenever Ganesh is flushed, so nothing is needed
-}