Timing Spec Updates

Per ACTION-36 Add a Vendor Prefix section to User Timing, ACTION-45 Look into updating the Timing specs to use type arrays from the Web IDL spec and other feedback, I have made the following spec updates:

Performance Timeline
Section 4.3 window.performance attribute updated to state that the methods return timing data in chronological order with respect to startTime.
Section 4.3 PerformanceEntryList interface removed and typedef sequence<PerformanceEntry> PerformanceEntryList added to performance interface definition.
WebIDL reference added.

User Timing
Section 4.5 Vendor Prefixes added

Resource Timing
setResourceTimingBufferSize method definition updated to scenario when maxSize is less than the number of parameters currently stored.

Page Visibility
Typos and markup issues fixed.
PAGE_PREVIEW should only be defined if supported.
Vendor prefix names should be in ASCII

Likewise, I have closed ACTION-36 and ACTION-45.

Thanks,
Jatinder