Move SkiaGpuContext creation in SkiaVkRenderEngine to virtual function

Making GaneshVkRenderEngine / GraphiteVkRenderEngine handle this reduces
the need for higher-level branching.

Test: boots successfully with skiavkthreaded
Bug: b/293371537
Change-Id: I5685cb9dd7b0dc1ce3a2d538a729c255fbd6c52b
diff --git a/libs/renderengine/skia/GaneshVkRenderEngine.cpp b/libs/renderengine/skia/GaneshVkRenderEngine.cpp
index 673ddf3..aa18713 100644
--- a/libs/renderengine/skia/GaneshVkRenderEngine.cpp
+++ b/libs/renderengine/skia/GaneshVkRenderEngine.cpp
@@ -34,6 +34,12 @@
     info->unref();
 }
 
+std::unique_ptr<SkiaGpuContext> GaneshVkRenderEngine::createContext(
+        VulkanInterface& vulkanInterface) {
+    return SkiaGpuContext::MakeVulkan_Ganesh(vulkanInterface.getGaneshBackendContext(),
+                                             mSkSLCacheMonitor);
+}
+
 void GaneshVkRenderEngine::waitFence(SkiaGpuContext* context, base::borrowed_fd fenceFd) {
     if (fenceFd.get() < 0) return;