don't error out when eglTerminate()ing an already terminated display

so says the EGL specification, section 3.2

Change-Id: Ice60530f8f6e47b4e14e06d2ab8eba799a7688a6

opengl/libs/EGL/egl_display.cpp

@@ -263,7 +263,13 @@ EGLBoolean egl_display_t::terminate() {
     Mutex::Autolock _l(lock);
 
     if (refs == 0) {
-        return setError(EGL_NOT_INITIALIZED, EGL_FALSE);
+        /*
+         * From the EGL spec (3.2):
+         * "Termination of a display that has already been terminated,
+         *  (...), is allowed, but the only effect of such a call is
+         *  to return EGL_TRUE (...)
+         */
+        return EGL_TRUE;
     }
 
     // this is specific to Android, display termination is ref-counted.