issue #163: review feedback

Author: panpan-lin

src/dropdown/dropdown.component.ts

@@ -30,8 +30,7 @@ import { I18n } from "./../i18n/i18n.module";
 	template: `
 	<div
 		class="bx--list-box"
-		[ngClass]="{'bx--dropdown--light': light}"
-	>
+		[ngClass]="{'bx--dropdown--light': theme === 'light'}">
 		<button
 			type="button"
 			#dropdownButton
@@ -86,10 +85,10 @@ export class Dropdown implements OnInit, AfterContentInit, OnDestroy {
 	 */
 	@Input() type: "single" | "multi" = "single";
 	/**
-	 * Set to `true` to apply the light style to the dropdown.
+	 * `light` or `dark` dropdown theme
 	 * @memberof Dropdown
 	 */
-	@Input() light = false;
+	@Input() theme: "light" | "dark" = "dark";
 	/**
 	 * Set to `true` to disable the dropdown.
 	 */

src/dropdown/dropdown.stories.ts

@@ -44,7 +44,7 @@ storiesOf("Dropdown", module)
 	.add("Light", () => ({
 		template: `
 		<ibm-dropdown
-			[light]="true"
+			[theme]="'light'"
 			placeholder="Select"
 			[disabled]="disabled"
 			(selected)="selected($event)"