Reporting print usage
Don't blindly trust toUnicode when building toFontChar for non-standard fonts without a font file (issue 4934)
Refactor fake worker loading (issue 3862)
Renames concatenateToArray to appendToArray
Telemetry for used stream and font types
Adds telemetry to record embedding usages
Merge pull request #4952 from yurydelendik/telemetry

Collect More Telemetry Data
Uplift for B2G bug 1009780 - Improve open mechanism for downloads.
Zero the height and width of the Cached canvases before deleting.

This reduces peak RSS by about 300 MiB on my Mac when scrolling slowly through
the first 30 pages of a scanned black and white document.
faster JPEG transform
Let Parser_makeFilter return NullStream when an invalid stream is encountered (issue 3417)
Merge pull request #4955 from timvandermeij/rename-concatenate

Renames concatenateToArray to appendToArray
Merge pull request #4959 from nnethercote/zero-cache-canvases

Zero the height and width of cached canvases before deleting them.
Merge pull request #4950 from fkaelberer/fasterJPEGtransform

Faster JPEG transform
Added getOperatorList to api.js
Merge pull request #4951 from pramodhkp/getoperatorlist

Added getOperatorList to api.js
Disables broken rAF on iOS
Merge pull request #4946 from Snuffleupagus/issue-3862

Refactor fake worker loading (issue 3862)
Increases page cache size when needed
Merge pull request #4962 from yurydelendik/issue-4943

Increases page cache size when needed