Describe the bug
When you create an exploration and reach the translation tab. Once you navigate out of the translation tab to another tab, then press the R button. The microphone access will be prompted by the browser. Found this while fixing #6708, when I was trying to test and refreshing my tab with the keyboard shortcut . Also occurs in develop branch.

To Reproduce
Steps to reproduce the behavior:

1. Create an exploration and go to 'Translation Tab'
2. Navigate away from the translation tab to another tab.
3. Press R
4. Browser will prompt for microphone access.

Observed behavior
The browser prompts for microphone access.

Expected behavior
You should only be prompted for microphone access on the translation tab.

Screenshots
If applicable, add screenshots to help explain your problem.

Desktop (please complete the following information; delete this section if the issue does not arise on desktop):

• OS: Ubuntu
• Browser: Chrome 74.0.3729.157 64 bit , Firefox 66.0.5 64 bit

Additional context
This only happens when you navigate to translation tab first, and then navigate out. The cause is the usage of document. Solution should use https://docs.angularjs.org/api/ng/directive/ngKeyup to isolate for the translation tab only.