First stab at requesting image data back from the GFX backend.

This also changes |BitmapData.draw| to be synchronous since they must complete before image data is requested.
Merge branch 'master' of https://github.com/mozilla/shumway into avx
Merge pull request #1581 from tschneidereit/master

Move setInterval, setTimeout, and Timer tests from tracetests to reftests harness
Disable HUD by default.
Fix AccessibilityProperties.
Merge pull request #1582 from mbebenita/avx

Avx
Fixes broken AS2 object construction
Merge pull request #1583 from tschneidereit/master

Fix SharedObject reftest
Disables AVM1 flash object for SWF v7 and below
Merge branch 'master' of github.com:mozilla/shumway
Avoid excess allocations in assert().

The use of `...args` caused TypeScript to emit some silly code that did
some unnecessary copying of the `arguments` array, and the use of
`arguments` caused additional allocations.

This change removes `...args`; only one message argument is now allowed,
and you have to pre-concatenate. This only affected ~20 assertions.

This reduces the cumulative allocations done by the JS engine while
starting up the racing demo by 34%, from 192 MB to 127 MB. These
allocations wouldn't happen in release mode, but there are so many of
them that it's worth fixing them even for non-release mode.
Merge pull request #1585 from nnethercote/slimmer-asserts

Avoid excess allocations in assert().
Moves AS2Utils.ts to the avm1lib
Merge pull request #1584 from yurydelendik/master

[AVM1] Fixes AS2Utils location, disables flash.* for SWF7, regression fix
Merge pull request #1589 from tschneidereit/master

Various fixes for tracetest-covered issues
Add support for dump().

I use dump() a lot for ad hoc profiling in the browser. This patch adds
a TypeScript declaration and a shell definition.
Merge pull request #1591 from nnethercote/add-dump

Add support for dump().
Don't execute AVM1 functions on VM failure
Fixes AVM1 toString()
Merge pull request #1598 from yurydelendik/master

Fixes several swfdec AVM1 tests