Implement terminal focus

src/vs/workbench/parts/terminal/electron-browser/terminal.ts

@@ -124,7 +124,7 @@ export interface ITerminalInstance {
 
 	dispose(): void;
 	copySelection(): void;
-	focus(): void;
+	focus(force?: boolean): void;
 	paste(): void;
 	sendText(text: string, addNewLine: boolean): void;
 	scrollDown(): void;

src/vs/workbench/parts/terminal/electron-browser/terminalInstance.ts

@@ -167,8 +167,15 @@ export class TerminalInstance implements ITerminalInstance {
 		this.onExitCallback(this);
 	}
 
-	public focus(): void {
-		// TODO: Implement
+	// TODO: Document, the purpose of force is not clear
+	public focus(force?: boolean): void {
+		if (!this.xterm) {
+			return;
+		}
+		let text = window.getSelection().toString();
+		if (!text || force) {
+			this.xterm.focus();
+		}
 	}
 
 	public paste(): void {

src/vs/workbench/parts/terminal/electron-browser/terminalService.ts

@@ -150,7 +150,7 @@ export class TerminalService implements ITerminalService {
 				});
 			} else {
 				if (focus) {
-					panel.focus();
+					this.getActiveInstance().focus(true);
 				}
 				complete(void 0);
 				//complete(<TerminalPanel>panel);