[Resource Timing] Spec feedback

I've been looking at implementing this again and made notes of some things
we might want to change in the spec. Let me know what you think.

"The startTime attribute must return..."

   - Why doesn't this just return fetchStart? I'd like the range [startTime,
   startTime + duration] to encompass all of the values in the struct (except
   for the zeroed out ones). As it is now, fetchStart may occur before
   startTime.

"The duration attribute must return a timestamp equal to the difference
between responseEnd and startTime, respectively."

   - This can be simplified to: "The duration attribute must return the
   difference between responseEnd and startTime."

"redirectStart attribute"
"redirectEnd attribute"

   - Can we put "Otherwise, ..." into its own paragraph? It'd make it easier
   to read, since each paragraph handles one condition.

Rest of the attributes (domainLookupStart, etc.)

   - Can we make these follow the same "if this..., if that...,
   otherwise..." structure as the redirect attributes? Right now, you just read
   the first paragraph and think you're done, not realizing there are
   exceptions listed after that.
   - Can we simplify the wording around the Timing-Allow-Origin? Maybe
   something along the lines of, "if the resource's origin doesn't satisfy the
   [resource origin check], return 0." Where [resource origin check] is a link
   to a separate section.

"void setResourceTimingBufferSize (in unsigned long maxSize);"

   - No space before the opening parenthesis.

"The callback onresourcetimingbufferfull is triggered when the buffer used
to store the list of PerformanceResourceTiming is full"

   - This should be more tightly defined: "The callback
   onresourcetimingbufferfull is called immediately after a resource is added
   to the buffer if the buffer size now equals the capacity." Or something
   along those lines.
   - It's not immediately clear from reading the text, but I think the
   intent is that this only fires once when the buffer becomes full and not for
   every resource loaded after that. We shouldn't spam developers with events
   if they don't care about Resource Timing.

"Have a value in the range of 100 to 200."

   - We have a 65K range. How about we push this out? Maybe make the high
   bit indicate it's vendor prefixed (32K - 64K).

Thanks,
James