Indeterminate progress

If I have:
```
<paper-progress></paper-progress>
```
The value is 0 (default) but the progress incorrectly shows as 100%.  One way to fix this is to set the default to scale(0).
```
#activeProgress, #secondaryProgress {
  -webkit-transform-origin: left center;
  transform-origin: left center;
  -webkit-transform: scale(0);
  transform: scale(0);
}

#activeProgress {
  background-color: #0f9d58;
}

#secondaryProgress {
  background-color: #87ceac;
}
```