UiPublicMember is now initialized with a statement.

Change-Id: I8b73d583be1ee7183f4074bce49d5390e38631a2

To avoid order-of-initialization problems.

Reviewed-by: Thomas Hartmann

Task-number: QTCREATORBUG-2306

Reviewed-by: Roberto Raggi

Unifying the api and exposing the options.

Missing files should be a warning.

The problem was that several lookup calls suddenly failed because
the actual QML types were no longer in the default scope chain. However,
the QML documentation says the type names are in the scope.

Also, 'MyComponent.' in a JS-expression context only showed the attached
properties of MyComponent and missed the enums.

With this change completion now may offers too many options, but that's
better than missing some.

This reverts parts of 490f2797

Reviewed-by: Leandro Melo

Reviewed-by: hjk

Each Components starts a new scope for ids. Using a stack to check
this properly.

We are checking for duplicate ids and duplicate property definitions now.

Reviewed-by: Erik Verbruggen

Also
* check the condition of the 'for(var' statement for assignment
* allow comma expressions in 'for(var'

Reviewed-by: Erik Verbruggen

Reviewed-by: Roberto Raggi

Reviewed-by: Roberto Raggi

Reviewed-by: Roberto Raggi

The "value might be 'undefined'" warning triggered whenever the static
expression evaluator failed to produce a value. At the moment, it does
so for almost all non-trivial expressions.

The warning is now disabled.

Task-number: QTCREATORBUG-3208

Task-number: QTCREATORBUG-3071
Reviewed-by: Erik Verbruggen

It still generates too many false-negatives for now. Will be enabled
once the remaining lookup failures have been fixed.

Reviewed-by: Erik Verbruggen

Reviewed-by: Erik Verbruggen

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.

Reviewed-by: Roberto Raggi

* If possible, create LookupContexts through SemanticInfo; it caches the
  linked Context and will be faster.
* Contexts now own their Engine.

Reviewed-by: Lasse Holmstedt

Reviewed-by: ckamm

Reviewed-by: ossi

Reviewed-by: Erik Verbruggen

Task-number: QTCREATORBUG-1439

Done-with: Erik Verbruggen

Use ScopeBuilder.push(...) for the same functionality.

Reviewed-by: Erik Verbruggen

Task-number: QTCREATORBUG-1021
Reviewed-by: Erik Verbruggen

Avoids bug where import errors would show up in all files.

Reviewed-by: Roberto Raggi