Guard against file protocol message in Firefox
Guard against file protocol message in Firefox

Firefox doesn’t have the same requirement for the file:// protocol
access, as well as Firefox has yet to implement the necessary
chrome.devtools.inspectedWindow.getResources API needed.  This change
avoids the use of that API in Firefox as it is unnecessary.

zalmoxisus/redux-devtools-extension,zalmoxisus/redux-devtools-extension