style: fix lint errors

Author: cupidi

src/lib/api/ext/class.ts

@@ -104,7 +104,8 @@ export class ClassDirective extends BaseFxDirective
 
     this._ngClassAdapter = new BaseFxDirectiveAdapter('ngClass', monitor, _ngEl, _renderer);
     this._classAdapter = new BaseFxDirectiveAdapter('class', monitor, _ngEl, _renderer);
-    this._classAdapter.cacheInput('class', isBrowser() ? _ngEl.nativeElement.getAttribute('class') || '' : '');
+    const classValue = isBrowser() ? _ngEl.nativeElement.getAttribute('class') || '' : '';
+    this._classAdapter.cacheInput('class', classValue);
 
     // Create an instance NgClass Directive instance only if `ngClass=""` has NOT been defined on
     // the same host element; since the responsive variations may be defined...

src/lib/api/ext/img-src.ts

@@ -58,7 +58,8 @@ export class ImgSrcDirective extends BaseFxDirective implements OnInit, OnChange
 
   constructor(elRef: ElementRef, renderer: Renderer2, monitor: MediaMonitor) {
     super(monitor, elRef, renderer);
-    this._cacheInput('src', isBrowser() ? elRef.nativeElement.getAttribute('src') || '' : '');
+    const srcValue = isBrowser() ? elRef.nativeElement.getAttribute('src') || '' : '';
+    this._cacheInput('src',  srcValue);
   }
 
   /**

src/lib/api/ext/style.ts

@@ -114,7 +114,8 @@ export class StyleDirective extends BaseFxDirective
 
     // Build adapter, `cacheInput()` interceptor, and get current inline style if any
     this._buildAdapter(this.monitor, _ngEl, _renderer);
-    this._base.cacheInput('style', isBrowser() ? _ngEl.nativeElement.getAttribute('style') || '' : '', true);
+    const styleValue = isBrowser() ? _ngEl.nativeElement.getAttribute('style') || '' : '';
+    this._base.cacheInput('style', styleValue, true);
 
     // Create an instance NgStyle Directive instance only if `ngStyle=""` has NOT been defined on
     // the same host element; since the responsive versions may be defined...