Update sky_server:
 - update its help string to admit that it wants the package path as well.
 - be quiet by default, since it makes the build chatty.
 - have a -v for verbose mode, for people who like it chatty.
 - have a default port of 8000, since that's what everyone used.
 - have a -p option to set the port, for people who don't use the default.
 - remove its mapping for gen/, since a TODO told me to.
 - remove the dependency on the build configuration, since it's no longer used.
 - teach it about .dart files.
 - rename sky_server/README to README.md, for consistency with other READMEs.
Update shelldb to speak the new sky_server protocol.
Update tests/services/iframe-embed-vmc.sky since the sky_server change broke the hack it was using.
Update skyserver.py to speak the new sky_server protocol.
Make webkitpy use SkyServer instead of spawning sky_server itself, since a TODO told me to.
Teach webkitpy about dart files.
Teach test_perf about dart files. (untested)
Teach sky_tool about main.dart, main.sky is deprecated. (untested)

R=eseidel@chromium.org

Review URL: https://codereview.chromium.org/1200993002.

TBR=ojan@chromium.org

Review URL: https://codereview.chromium.org/1037163002

1) Merge input example into widgets example
2) Move single-file, non-fn examples into a "raw" directory
3) Rename stocks-fn and widgets-fn to stocks and widgets

R=ojan@chromium.org

Review URL: https://codereview.chromium.org/1005393006

R=ojan@chromium.org

Review URL: https://codereview.chromium.org/1030063003

Just use promise chaining

Eventually all of this should be moved out of Sky
and instead sit on top of Sky as just a mojo v8 debug service
but for now I'm just bringing back what we had in Blink
so I can make it work with our new inspector backend
and then we can move it out.

I also sorted gn lists and fixed two .idl files
which were in the wrong sources list in core.gni.

R=abarth@chromium.org, yurys@chromium.org

Review URL: https://codereview.chromium.org/723773002

R=abarth@chromium.org

Review URL: https://codereview.chromium.org/701933004

parsed' callback; pass the element's module to the constructor when
constructing a custom element (these are rather experimental changes
and we may want to go a different way on this stuff)

Review URL: https://codereview.chromium.org/701873004

exported and reexported, rename 'interface' to 'class' in the IDL, add
constructors to all registered elements

R=esprehn@chromium.org

Review URL: https://codereview.chromium.org/695043002

Review URL: https://codereview.chromium.org/678693003

R=ojan@chromium.org

Review URL: https://codereview.chromium.org/679583002

R=jamesr@chromium.org

Review URL: https://codereview.chromium.org/672963002