On Android enable always fast

Invert the meaning of holding down the fast button (i.e. holding down the fast button -- if there is one -- means walk), unless performing an action, sneaking or jumping.
Still requires fast move to be toggled on (and fast priv)

src/game.cpp

@@ -2969,9 +2969,8 @@ void Game::updatePlayerControl(const CameraOrientation &cam)
 		cam.camera_pitch,
 		cam.camera_yaw
 	);
-	client->setPlayerControl(control);
+
-	LocalPlayer *player = client->getEnv().getLocalPlayer();
+	u32 keypress_bits =
-	player->keyPressed =
 			( (u32)(input->isKeyDown(keycache.key[KeyCache::KEYMAP_ID_FORWARD])  & 0x1) << 0) |
 			( (u32)(input->isKeyDown(keycache.key[KeyCache::KEYMAP_ID_BACKWARD]) & 0x1) << 1) |
 			( (u32)(input->isKeyDown(keycache.key[KeyCache::KEYMAP_ID_LEFT])     & 0x1) << 2) |
@@ -2983,6 +2982,25 @@ void Game::updatePlayerControl(const CameraOrientation &cam)
 			( (u32)(input->getRightState()                                       & 0x1) << 8
 		);
 
+#ifdef ANDROID
+	/* For Android, invert the meaning of holding down the fast button (i.e.
+	 * holding down the fast button -- if there is one -- means walk), unless
+	 * performing an action, sneaking or jumping.
+	 */
+	const u32 autofast_exludebits =
+			  (1U << 4) | (1U << 6)     // jump, sneak
+			| (1U << 7) | (1U << 8);    // left state, right state
+
+	if ((keypress_bits & autofast_exludebits) == 0) {
+		control.aux1 = control.aux1 ^ true;
+		keypress_bits ^= ((u32)(1U << 5));
+	}
+#endif
+
+	client->setPlayerControl(control);
+	LocalPlayer *player = client->getEnv().getLocalPlayer();
+	player->keyPressed = keypress_bits;
+
 	//tt.stop();
 }