Fix Google Maps overlay (#1263)

* Fix imageSource.url init

* Fix constructor typings

* More typings fixes

* Reintroduce optional sessionOptions on GoogleCloudAuthPlugin for 3d tiles use where it is not needed

Author: xawill

src/three/plugins/GoogleCloudAuthPlugin.d.ts

@@ -5,7 +5,7 @@ export class GoogleCloudAuthPlugin {
 		autoRefreshToken?: boolean,
 		logoUrl?: string,
 		useRecommendedSettings?: boolean;
-		sessionOptions?: null | { mapType: string, language: string, region: string },
+		sessionOptions?: null | { mapType: string, language: string, region: string, [key: string]: any },
 	} );
 
 }

src/three/plugins/images/ImageOverlayPlugin.d.ts

@@ -85,7 +85,7 @@ export class GoogleMapsOverlay extends ImageOverlay {
 		apiToken: string,
 		autoRefreshToken?: boolean,
 		logoUrl?: string,
-		sessionOptions?: null | { mapType: string, language: string, region: string },
+		sessionOptions: { mapType: string, language: string, region: string, [key: string]: any },
 
 		color: number | Color,
 		opacity: number,

src/three/plugins/images/ImageOverlayPlugin.js

@@ -1615,7 +1615,7 @@ export class GoogleMapsOverlay extends ImageOverlay {
 			.then( json => {
 
 				this.imageSource.tileDimension = json.tileWidth;
-				this.imageSource = 'https://tile.googleapis.com/v1/2dtiles/{z}/{x}/{y}';
+				this.imageSource.url = 'https://tile.googleapis.com/v1/2dtiles/{z}/{x}/{y}';
 				return this.imageSource.init();
 
 			} );