Link now caches imports. That means importing the same library (say, Qt)
from more than one file no longer creates an importing namespace for
each one. Instead, a single one is created for the instance of Link.

To make this work, the type environment in ScopeChain has been given its
own type: Interpreter::TypeEnvironment. That has the added benefit of
being able to carry meta-information about imports. You can use
TypeEnvironment::importInfo(qmlComponentName) to get information about
the import node that caused the import of the component.

Don't use QMultiHash::values(key), it rebuilds the values list from
scratch for each lookup.

Reviewed-by: Roberto Raggi

Reviewed-by: Erik Verbruggen

Task-number: QTCREATORBUG-1421
Reviewed-by: Erik Verbruggen

When adding a new file, refreshing semantic errors in the open editor should
have worked. It now also works for removing existing files.

Done-with: Christian Kamm

When adding a new file, refreshing semantic errors in the open editor should
have worked. It now also works for removing existing files.

Done-with: Christian Kamm

Previously, fresh versions of a Document would be added to the
_documentsByPath QMultiHash without removing the old version first.
This means Link could pick up old versions of a Document.

Task-number: QTCREATORBUG-1418

To solve import resolution issues on windows.

Reviewed-by: Roberto Raggi

Using canonical paths breaks with symlinked components. Also the editor
filename isn't canonical, so comparing them breaks.

This reverts commit efcdadd2.

Also change the filename->document map to a hash.

Reviewed-by: Roberto Raggi

Otherwise the paths may end up with ../ or /./ in them and confuse the
Qml import resolving.

Reviewed-by: Thomas Hartmann

Reviewed-by: ckamm

The Document thought it was a JS file as it doesn't have the .qml
extension.

Reviewed-by: Erik Verbruggen

* Add SemanticHighlighter to QmlJSTextEditor to update the semantic info
  in a background thread.
* Add QmlJS::Check to run semantic checks on qml and js documents.
* Add a check for incorrect property names.
* Fix hoverhandler to show tool tips from extra selections over help
  tooltips.

There is no reason to store the Bind object in a QSharedPointer because the `binder' has the same
lifetime of its document.

Reviewed-by: Roberto Raggi <roberto.raggi@nokia.com>

Done with: Erik

Done-with: Christian Kamm

Ideally most of our visitors won't need to make the QML vs JS
distinction. For these cases it'll be handy to be able to access the AST
no matter whether it's a Program or UiProgram.

Changed the QML/JS editor to treat .qs/.js files as JavaScript, and invoke the appropriate parser for it.

Reviewed-by: Christian Kamm

Fix namespace usage such that all classes in shared/qml live in the
Qml namespace, and classes in QmlDesigner plugin in the QmlDesigner
namespace.

This should prevent any symbol clashes until we can finally get rid
of the file dublicates (e.g. QmlDocument).