perf(material/tooltip): Avoid unneeded calls to clearTimeout (#29643)

Author: kseamon

src/material/tooltip/tooltip.ts

@@ -354,7 +354,7 @@ export class MatTooltip implements OnDestroy, AfterViewInit {
   private _document: Document;
 
   /** Timer started at the last `touchstart` event. */
-  private _touchstartTimeout: ReturnType<typeof setTimeout>;
+  private _touchstartTimeout: null | ReturnType<typeof setTimeout> = null;
 
   /** Emits when the component is destroyed. */
   private readonly _destroyed = new Subject<void>();
@@ -434,7 +434,10 @@ export class MatTooltip implements OnDestroy, AfterViewInit {
   ngOnDestroy() {
     const nativeElement = this._elementRef.nativeElement;
 
-    clearTimeout(this._touchstartTimeout);
+    // Optimization: Do not call clearTimeout unless there is an active timer.
+    if (this._touchstartTimeout) {
+      clearTimeout(this._touchstartTimeout);
+    }
 
     if (this._overlayRef) {
       this._overlayRef.dispose();
@@ -802,13 +805,15 @@ export class MatTooltip implements OnDestroy, AfterViewInit {
           // Note that it's important that we don't `preventDefault` here,
           // because it can prevent click events from firing on the element.
           this._setupPointerExitEventsIfNeeded();
-          clearTimeout(this._touchstartTimeout);
+          if (this._touchstartTimeout) {
+            clearTimeout(this._touchstartTimeout);
+          }
 
           const DEFAULT_LONGPRESS_DELAY = 500;
-          this._touchstartTimeout = setTimeout(
-            () => this.show(undefined, origin),
-            this._defaultOptions.touchLongPressShowDelay ?? DEFAULT_LONGPRESS_DELAY,
-          );
+          this._touchstartTimeout = setTimeout(() => {
+            this._touchstartTimeout = null;
+            this.show(undefined, origin);
+          }, this._defaultOptions.touchLongPressShowDelay ?? DEFAULT_LONGPRESS_DELAY);
         },
       ]);
     }
@@ -839,7 +844,9 @@ export class MatTooltip implements OnDestroy, AfterViewInit {
     } else if (this.touchGestures !== 'off') {
       this._disableNativeGesturesIfNecessary();
       const touchendListener = () => {
-        clearTimeout(this._touchstartTimeout);
+        if (this._touchstartTimeout) {
+          clearTimeout(this._touchstartTimeout);
+        }
         this.hide(this._defaultOptions.touchendHideDelay);
       };