Fix lint warnings (#1170)

* Fix lint warnings

* Format

* Fix build on CI

Author: justinfagnani

src/lit-element.ts

@@ -133,7 +133,7 @@ export class LitElement extends UpdatingElement {
   static styles?: CSSResultOrNative|CSSResultArray;
 
   /** @nocollapse */
-  static shadowRootOptions: ShadowRootInit = { mode: "open" };
+  static shadowRootOptions: ShadowRootInit = {mode: 'open'};
 
   private static _styles: Array<CSSResultOrNative|CSSResult>|undefined;
 
@@ -240,7 +240,7 @@ export class LitElement extends UpdatingElement {
    */
   protected createRenderRoot(): Element|ShadowRoot {
     return this.attachShadow(
-      (this.constructor as typeof LitElement).shadowRootOptions);
+        (this.constructor as typeof LitElement).shadowRootOptions);
   }
 
   /**

src/test/lit-element_styling_test.ts

@@ -130,7 +130,7 @@ suite('Styling', () => {
       }
 
       firstUpdated() {
-        this.inner = this.shadowRoot!.querySelector('x-inner')! as LitElement;
+        this.inner = this.shadowRoot!.querySelector('x-inner') as LitElement;
       }
     }
     customElements.define(name, E);

src/test/lit-element_test.ts

@@ -291,16 +291,14 @@ suite('LitElement', () => {
       });
 
   (window.ShadyDOM && window.ShadyDOM.inUse ? test.skip : test)(
-      "can customize shadowRootOptions",
-      async () => {
+      'can customize shadowRootOptions', async () => {
         class A extends LitElement {
-          static shadowRootOptions: ShadowRootInit = { mode: "closed" };
+          static shadowRootOptions: ShadowRootInit = {mode: 'closed'};
         }
         customElements.define(generateElementName(), A);
         const a = new A();
         container.appendChild(a);
         await a.updateComplete;
         assert.equal(a.shadowRoot, undefined);
-      }
-    );
+      });
 });