chore(typings): remove StringMap

This was a poorly typed attempt to mimic TypeScript's index signatures,
which we can use instead.
This eliminates a very strange type that we were exposing to users, but
not re-exporting through our public API.

Fixes #4483

modules/angular2/src/animate/animation.ts

@@ -96,7 +96,7 @@ export class Animation {
    * Applies the provided styles to the element
    * @param styles
    */
-  applyStyles(styles: StringMap<string, any>): void {
+  applyStyles(styles: {[key: string]: any}): void {
     StringMapWrapper.forEach(styles, (value, key) => {
       var dashCaseKey = camelCaseToDashCase(key);
       if (isPresent(DOM.getStyle(this.element, dashCaseKey))) {

modules/angular2/src/animate/css_animation_builder.ts

@@ -61,7 +61,7 @@ export class CssAnimationBuilder {
    * @param from
    * @param to
    */
-  setStyles(from: StringMap<string, any>, to: StringMap<string, any>): CssAnimationBuilder {
+  setStyles(from: {[key: string]: any}, to: {[key: string]: any}): CssAnimationBuilder {
     return this.setFromStyles(from).setToStyles(to);
   }
 
@@ -69,7 +69,7 @@ export class CssAnimationBuilder {
    * Sets the initial styles for the animation
    * @param from
    */
-  setFromStyles(from: StringMap<string, any>): CssAnimationBuilder {
+  setFromStyles(from: {[key: string]: any}): CssAnimationBuilder {
     this.data.fromStyles = from;
     return this;
   }
@@ -78,7 +78,7 @@ export class CssAnimationBuilder {
    * Sets the destination styles for the animation
    * @param to
    */
-  setToStyles(to: StringMap<string, any>): CssAnimationBuilder {
+  setToStyles(to: {[key: string]: any}): CssAnimationBuilder {
     this.data.toStyles = to;
     return this;
   }

modules/angular2/src/animate/css_animation_options.ts

@@ -1,9 +1,9 @@
 export class CssAnimationOptions {
   /** initial styles for the element */
-  fromStyles: StringMap<string, any>;
+  fromStyles: {[key: string]: any};
 
   /** destination styles for the element */
-  toStyles: StringMap<string, any>;
+  toStyles: {[key: string]: any};
 
   /** classes to be added to the element */
   classesToAdd: string[] = [];