[HTML5] Fix focus (again) in Firefox's iframes.

This actually makes sense(?), when running inside an iframe the active
element might be our canvas, while the iframe itself is not active in
the parent window. Since we consume the event, the iframe does not get
focused in Firefox (but does in Chromium-based browsers), so we must
always call focus to handle such occasions.

(cherry picked from commit 63e2db249901312f317c45df8dffbf06e43b3c4a)

platform/javascript/js/libs/library_godot_input.js

@@ -393,7 +393,9 @@ const GodotInput = {
 			const rect = canvas.getBoundingClientRect();
 			const pos = GodotInput.computePosition(evt, rect);
 			const modifiers = GodotInput.getModifiers(evt);
-			if (p_pressed && document.activeElement !== GodotConfig.canvas) {
+			// Since the event is consumed, focus manually.
+			// NOTE: The iframe container may not have focus yet, so focus even when already active.
+			if (p_pressed) {
 				GodotConfig.canvas.focus();
 			}
 			if (func(p_pressed, evt.button, pos[0], pos[1], modifiers)) {
@@ -412,7 +414,9 @@ const GodotInput = {
 		const func = GodotRuntime.get_func(callback);
 		const canvas = GodotConfig.canvas;
 		function touch_cb(type, evt) {
-			if (type === 0 && document.activeElement !== GodotConfig.canvas) {
+			// Since the event is consumed, focus manually.
+			// NOTE: The iframe container may not have focus yet, so focus even when already active.
+			if (type === 0) {
 				GodotConfig.canvas.focus();
 			}
 			const rect = canvas.getBoundingClientRect();