Allow Windows to use system Vsync if only one window is swapping

ui/gl/gl_context_egl.cc

Index: ui/gl/gl_context_egl.cc
diff --git a/ui/gl/gl_context_egl.cc b/ui/gl/gl_context_egl.cc
index 733ad8d85a2cced84f93a6492f8fdafe3b2a67bf..41c10dcff3cd58f41dea5d7c5b9822b09e536119 100644
--- a/ui/gl/gl_context_egl.cc
+++ b/ui/gl/gl_context_egl.cc
@@ -183,6 +183,8 @@ void GLContextEGL::SetSwapInterval(int interval) {
   if (!eglSwapInterval(display_, interval)) {
     LOG(ERROR) << "eglSwapInterval failed with error "
                << GetLastEGLErrorString();
+  } else {
+    GLSurface::GetCurrent()->SetSwapInterval(interval);
   }
 }