fixup! Firefox preference overrides.

Bug 42830: Enable Web Audio API.

We were concerned about fingerprintability of these APIs.
However, Mozilla switched to the same Math library for all platforms, so
these concerns are less reduced (and are mostly about different
architectures, that probably leak anyway).
So, for compatibility, we decided to enable Web Audio.

browser/app/profile/001-base-profile.js

@@ -377,8 +377,7 @@ pref("dom.disable_window_move_resize", true);
 // Set video VP9 to 0 for everyone (bug 22548)
 pref("media.benchmark.vp9.threshold", 0);
 pref("privacy.resistFingerprinting.block_mozAddonManager", true); // Bug 26114
-pref("dom.webaudio.enabled", false); // Bug 13017: Disable Web Audio API
-pref("dom.webmidi.enabled", false); //  Bug 41398: Disable Web MIDI API
+pref("dom.webmidi.enabled", false); // Bug 41398: Disable Web MIDI API
 // tor-browser#42043: Stop reporting device IDs (and spoof their number without
 // RFP, RFP already reports 1 audioinput and 1 videoinput, but still has
 // randomized IDs when this pref is true).