Improve startup benchmarking

Move the benchmarking measuring methods from `Engine` to `OS` to allow for platform specific overrides (e.g: can be used to hook into platform specific benchmarking and tracing capabilities).

platform/android/java/editor/src/main/java/org/godotengine/editor/GodotEditor.kt

@@ -113,6 +113,9 @@ open class GodotEditor : FullScreenGodotApp() {
 		if (args != null && args.isNotEmpty()) {
 			commandLineParams.addAll(listOf(*args))
 		}
+		if (BuildConfig.BUILD_TYPE == "dev") {
+			commandLineParams.add("--benchmark")
+		}
 	}
 
 	override fun getCommandLine() = commandLineParams