Make the I Tried star appear when a top-level page load fails for network-related reasons.

Under the hood, this requires treating the I Tried pipeline as a new load instead of a replacement, since the failure-handling code interacts poorly with the rest of the replacement code when we get a series of staggered failures over time from the various pipeline components.
auto merge of #2200 : jdm/servo/loadfail, r=mbrubeck

...k-related reasons.

Under the hood, this requires treating the I Tried pipeline as a new load instead of a replacement, since the failure-handling code interacts poorly with the rest of the replacement code when we get a series of staggered failures over time from the various pipeline components.
Add NodeHelpers::get_bounding_content_box().
Add NodeHelpers::get_content_boxes().
Add Page::hit_test().
Add Page::get_nodes_under_mouse().
auto merge of #2210 : saneyuki/servo/query, r=jdm

- see #356
- To decrease the conversion code, `JS<Node>` -> `Node`, I added API methods to `NodeHelpers`.
- I added APIs to `Page` not `Document` because I had thought that their APIs returns the hitted nodes address in the "page".
Ensure Node.Normalize() acts on all descendants by recursively calling it on all non-text child nodes.
auto merge of #2221 : hazz/servo/normalize, r=jdm

Fixes #2170 by recursively calling `normalize()` on all children that aren't text nodes.
Set default scale based on dpi
Add support for dictionaries containing 'any'.
Move assignments outside match expressions in getJSToNativeConversionTemplate.

This is a first step towards making getJSToNativeConversionTemplate return an
expression, which will improve dictionary codegen in particular.
auto merge of #2224 : mbrubeck/servo/hidpi, r=metajack

On high-density (e.g. "Retina") displays, this will set the default scale to 1 px per screen coordinate, rather than the current 1px per hardware pixel. This means that content on high-density displays will be rendered at a higher resolution but about the same physical size, compared to lower-density displays.
Pass extra args through to wptrunner
auto merge of #2225 : Ms2ger/servo/any-dictionary, r=jdm
auto merge of #2216 : jgraham/servo/extra_args_wptrunner, r=jack
Move responsability for the assignment out of CastableObjectUnwrapper.

This is a second step towards making getJSToNativeConversionTemplate return an
expression, which will improve dictionary codegen in particular.

This commit does not make any change to the generated code.
Inline CGAbstractBindingMethod.getThis.

There's no good reason to keep this separate; it's only called once, and
inlining the function makes the code a little clearer.

This commit does not make any change to the generated code.
Assign to 'this' immediately in CGAbstractBindingMethod.

This makes the generated code a bit more rustic.
auto merge of #2227 : Ms2ger/servo/assign-outside-match, r=jdm