Move color to common, work with IColor

IColor is needed for the minimum contrast ratio function currently.

src/browser/Types.d.ts

@@ -5,11 +5,10 @@
 
 import { IDecorationOptions, IDecoration, IDisposable, IMarker, ISelectionPosition } from 'xterm';
 import { IEvent } from 'common/EventEmitter';
-import { ICoreTerminal, CharData, ITerminalOptions } from 'common/Types';
+import { ICoreTerminal, CharData, ITerminalOptions, IColor } from 'common/Types';
 import { IMouseService, IRenderService } from './services/Services';
 import { IBuffer } from 'common/buffer/Types';
 import { IFunctionIdentifier, IParams } from 'common/parser/Types';
-import { createDecorator } from 'common/services/ServiceRegistry';
 
 export interface ITerminal extends IPublicTerminal, ICoreTerminal {
   element: HTMLElement | undefined;
@@ -113,11 +112,6 @@ export interface IColorManager {
   onOptionsChange(key: string): void;
 }
 
-export interface IColor {
-  css: string;
-  rgba: number; // 32-bit int with rgba in each byte
-}
-
 export interface IColorSet {
   foreground: IColor;
   background: IColor;