Show placeholder text in testing view progress area (fix microsoft#141181) (microsoft#188484)

* Show placeholder text in testing view progress area (fix microsoft#141181)

* Use blank placeholder

Author: gjsjohnmurray

src/vs/workbench/contrib/testing/browser/testingExplorerView.ts

@@ -290,6 +290,7 @@ export class TestingExplorerView extends ViewPane {
 			this.countSummary = text;
 			this.renderActivityCount();
 		}));
+		this.testProgressService.update();
 
 		const listContainer = dom.append(this.container, dom.$('.test-explorer-tree'));
 		this.viewModel = this.instantiationService.createInstance(TestingExplorerViewModel, listContainer, this.onDidChangeBodyVisibility);

src/vs/workbench/contrib/testing/browser/testingProgressUiService.ts

@@ -115,7 +115,7 @@ export class TestingProgressUiService extends Disposable implements ITestingProg
 				this.updateCountsEmitter.fire(collected);
 				this.updateTextEmitter.fire(getTestProgressText(false, collected));
 			} else {
-				this.updateTextEmitter.fire('');
+				this.updateTextEmitter.fire('\xA0');
 				this.updateCountsEmitter.fire(collectTestStateCounts(false));
 			}