src/goExplorer.ts: show go explorer on extension activation

Fixes #2202.

Change-Id: I330092739089031848cf9f17a6b031590b9d61c3
Reviewed-on: https://go-review.googlesource.com/c/vscode-go/+/401614
Run-TryBot: Jamal Carvalho <[email protected]>
Reviewed-by: Hyang-Ah Hana Kim <[email protected]>
TryBot-Result: kokoro <[email protected]>
Reviewed-by: Jamal Carvalho <[email protected]>
Auto-Submit: Jamal Carvalho <[email protected]>

Author: jamalc

package.json

@@ -2742,7 +2742,8 @@
         {
           "id": "go.explorer",
           "name": "go",
-          "icon": "media/go-logo-white.svg"
+          "icon": "media/go-logo-white.svg",
+          "when": "go.showExplorer"
         }
       ],
       "test": [

src/goExplorer.ts

@@ -26,13 +26,14 @@ export class GoExplorerProvider implements vscode.TreeDataProvider<vscode.TreeIt
 		const provider = new this();
 		const {
 			window: { registerTreeDataProvider },
-			commands: { registerCommand }
+			commands: { registerCommand, executeCommand }
 		} = vscode;
 		subscriptions.push(registerTreeDataProvider('go.explorer', provider));
 		subscriptions.push(registerCommand('go.explorer.refresh', () => provider.update(true)));
 		subscriptions.push(registerCommand('go.explorer.open', (item) => provider.open(item)));
 		subscriptions.push(registerCommand('go.workspace.editEnv', (item) => provider.editEnv(item)));
 		subscriptions.push(registerCommand('go.workspace.resetEnv', (item) => provider.resetEnv(item)));
+		executeCommand('setContext', 'go.showExplorer', true);
 		return provider;
 	}