Capture/Replay: Rework trace EGLDisplay handling

Refactor the trace-replay EGLDisplay handling to allow
initializing the global EGLDisplay handle in the
InitializeReplay4() body. This included adding
support for eglGetCurrentDisplay() to the EGL-on-
WGL shim.

Test: angle_trace_tests --gtest_filter=infinity_ops
Bug: b/282725258
Change-Id: I2319fd9a35f8fb9c0a7f10547ca39f49ce402b8d
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/4546267
Reviewed-by: Roman Lavrov <romanl@google.com>
Reviewed-by: Cody Northrop <cnorthrop@google.com>
Commit-Queue: Mark Łobodziński <mark@lunarg.com>

util/EGLWindow.cpp

@@ -816,6 +816,11 @@ EGLint EGLWindow::getEGLError()
     return eglGetError();
 }
 
+EGLWindow::Display EGLWindow::getCurrentDisplay()
+{
+    return eglGetCurrentDisplay();
+}
+
 GLWindowBase::Surface EGLWindow::createPbufferSurface(const EGLint *attrib_list)
 {
     return eglCreatePbufferSurface(getDisplay(), getConfig(), attrib_list);