Start RenderThread earlier to preload Vulkan/EGL drivers

This CL should fix application startup regression for Vulkan
detected by "Hermetic Startup: EmptyActivity" test.
EGL drivers are loaded in a temp thread to leave more time
in RenderThread for other work. Loading EGL drivers
on the RenderThread may cause a perf regression.

Test: Ran cold-dropcache-test test.
Bug: 122659224
Bug: 123361175
Change-Id: I8ca818e98fac196a41d079be15594caca5cb1bab
diff --git a/libs/hwui/renderthread/RenderProxy.cpp b/libs/hwui/renderthread/RenderProxy.cpp
index 720c603..34f76d9 100644
--- a/libs/hwui/renderthread/RenderProxy.cpp
+++ b/libs/hwui/renderthread/RenderProxy.cpp
@@ -381,6 +381,14 @@
     });
 }
 
+void RenderProxy::preload() {
+    // Create RenderThread object and start the thread. Then preload Vulkan/EGL driver.
+    auto& thread = RenderThread::getInstance();
+    thread.queue().post([&thread]() {
+        thread.preload();
+    });
+}
+
 } /* namespace renderthread */
 } /* namespace uirenderer */
 } /* namespace android */