As discussed in IRC, we are migrating our IDL files away from the interface-level "LegacyDefaultOptionalArguments" flag and onto argument-level [Optional] or [Optional=CallWithDefaultValue] flags. This patch migrates all remaining webaudio-related IDL files. This patch CHANGES BEHAVIOR, specifically it makes all arguments required in the noteOn(), noteGrainOn(), and noteOff() methods of AudioBufferSourceNode. This is in line with other changes already made to other parts of the web audio API which made all arguments required (for example, in AudioBuffer), so I'm assuming that this IDL file just got missed.
AFAIK, web audio has no tests yet.
Created attachment 103040 [details]
Comment on attachment 103040 [details]
Clearing flags on attachment: 103040
Committed r92459: <http://trac.webkit.org/changeset/92459>
All reviewed patches have been landed. Closing bug.
I wish I had been on the CC list for this, because it was the intention that this argument should be optional (although admittedly the spec isn't clear about this).
I'm not sure which API you mean specifically, but Its easy to fix.