Mute progress animation while Git is running so it doesn't overwrite credential prompts.

sdk/lib/_internal/pub/lib/src/progress.dart

Index: sdk/lib/_internal/pub/lib/src/progress.dart
diff --git a/sdk/lib/_internal/pub/lib/src/progress.dart b/sdk/lib/_internal/pub/lib/src/progress.dart
index 6c0ffdcf2f2dc3d8330991cf503082ad49702692..5029f61af9b4ee4ffc754b3ea9edb988320a9e9e 100644
--- a/sdk/lib/_internal/pub/lib/src/progress.dart
+++ b/sdk/lib/_internal/pub/lib/src/progress.dart
@@ -48,10 +48,11 @@ class Progress {
       return;
     }
 
-    _update();
     _timer = new Timer.periodic(new Duration(milliseconds: 100), (_) {
       _update();
     });
+
+    _update();
   }
 
   /// Stops the progress indicator.
@@ -88,11 +89,11 @@ class Progress {
 
   /// Refreshes the progress line.
   void _update() {
+    if (log.isMuted) return;
+
     stdout.write(log.format("\r$_message... "));
 
     // Show the time only once it gets noticeably long.
-    if (_stopwatch.elapsed.inSeconds > 0) {
-      stdout.write(log.gray(_time));
-    }
+    if (_stopwatch.elapsed.inSeconds > 0) stdout.write("${log.gray(_time)} ");
   }
 }