Make terminal access APIs stable

Fixes #52574

src/vs/vscode.d.ts

@@ -5784,6 +5784,17 @@ declare module 'vscode' {
 		 */
 		export const onDidChangeTextEditorViewColumn: Event<TextEditorViewColumnChangeEvent>;
 
+		/**
+		 * The currently opened terminals or an empty array.
+		 */
+		export const terminals: ReadonlyArray<Terminal>;
+
+		/**
+		 * An [event](#Event) which fires when a terminal has been created, either through the
+		 * [createTerminal](#window.createTerminal) API or commands.
+		 */
+		export const onDidOpenTerminal: Event<Terminal>;
+
 		/**
 		 * An [event](#Event) which fires when a terminal is disposed.
 		 */

src/vs/vscode.proposed.d.ts

@@ -615,11 +615,6 @@ declare module 'vscode' {
 	}
 
 	export namespace window {
-		/**
-		 * The currently opened terminals or an empty array.
-		 */
-		export const terminals: ReadonlyArray<Terminal>;
-
 		/**
 		 * The currently active terminal or `undefined`. The active terminal is the one that
 		 * currently has focus or most recently had focus.
@@ -633,12 +628,6 @@ declare module 'vscode' {
 		 */
 		export const onDidChangeActiveTerminal: Event<Terminal | undefined>;
 
-		/**
-		 * An [event](#Event) which fires when a terminal has been created, either through the
-		 * [createTerminal](#window.createTerminal) API or commands.
-		 */
-		export const onDidOpenTerminal: Event<Terminal>;
-
 		/**
 		 * Create a [TerminalRenderer](#TerminalRenderer).
 		 *

src/vs/workbench/api/node/extHost.api.impl.ts

@@ -335,7 +335,7 @@ export function createApiFactory(
 				return proposedApiFunction(extension, extHostTerminalService.activeTerminal);
 			},
 			get terminals() {
-				return proposedApiFunction(extension, extHostTerminalService.terminals);
+				return extHostTerminalService.terminals;
 			},
 			showTextDocument(documentOrUri: vscode.TextDocument | vscode.Uri, columnOrOptions?: vscode.ViewColumn | vscode.TextDocumentShowOptions, preserveFocus?: boolean): TPromise<vscode.TextEditor> {
 				let documentPromise: TPromise<vscode.TextDocument>;
@@ -372,9 +372,9 @@ export function createApiFactory(
 			onDidCloseTerminal(listener, thisArg?, disposables?) {
 				return extHostTerminalService.onDidCloseTerminal(listener, thisArg, disposables);
 			},
-			onDidOpenTerminal: proposedApiFunction(extension, (listener, thisArg?, disposables?) => {
+			onDidOpenTerminal(listener, thisArg?, disposables?) {
 				return extHostTerminalService.onDidOpenTerminal(listener, thisArg, disposables);
-			}),
+			},
 			onDidChangeActiveTerminal: proposedApiFunction(extension, (listener, thisArg?, disposables?) => {
 				return extHostTerminalService.onDidChangeActiveTerminal(listener, thisArg, disposables);
 			}),