Reorder eager extension activation (#176706)

* Handle all pending operations right after opening barrier

---------

Co-authored-by: Alexandru Dima <alexdima@microsoft.com>

src/vs/workbench/api/common/extHostExtensionActivator.ts

@@ -193,6 +193,14 @@ export class ExtensionsActivator implements IDisposable {
 		}
 	}
 
+	public async waitForActivatingExtensions(): Promise<void> {
+		const res: Promise<boolean>[] = [];
+		for (const [_, op] of this._operations) {
+			res.push(op.wait());
+		}
+		await Promise.all(res);
+	}
+
 	public isActivated(extensionId: ExtensionIdentifier): boolean {
 		const op = this._operations.get(extensionId);
 		return Boolean(op && op.value);

src/vs/workbench/api/common/extHostExtensionService.ts

@@ -756,6 +756,10 @@ export abstract class AbstractExtHostExtensionService extends Disposable impleme
 
 		return this._readyToStartExtensionHost.wait()
 			.then(() => this._readyToRunExtensions.open())
+			.then(() => {
+				// wait for all activation events that came in during workbench startup, but at maximum 1s
+				return Promise.race([this._activator.waitForActivatingExtensions(), timeout(1000)]);
+			})
 			.then(() => this._handleEagerExtensions())
 			.then(() => {
 				this._eagerExtensionsActivated.open();