Mostly just a revert of the commit that removed this functionality, with a few changes:
* Perform proper JavaScript encoding in the script part of the database error page Views/BaseView.cs
* Use the builder pattern in the UseXyz extension methods on IApplicationBuilder (per #184). Also applying this to DatabaseErrorPageOptions to keep things consistent.
* Fixing a few tests that were getting the context from DI but putting it in a using block so that it got disposed (rather than letting DI handle disposing).
When there is an existing database and no migrations are present, then we should just display the standard error page as they are not using migrations and need to adjust their mapping code to match the existing schema.
Resolve#182
- avoid `cmd /C dnvm.cmd ...` because `cmd` does not report `.cmd` script exit code correctly
- change both `_dnu.shade` and `_k.shade` though `_k.shade` is more-often an issue
- @moozzyk reported problem in [discussion](https://github.com/aspnet/Universe/pull/299#discussion-diff-41954492) of PR #299
- `TagHelper`s used to not flatten correctly resulting in inconsistent start locations for `SyntaxTreeNode`s following/within `TagHelper`s.
- This change indirectly corrected bad indentation that existed in generated C#.
- Added a test to validate `TreesAreDifferent` returns expected behavior when modifying content inside of `TagHelper`.
- Added `TagHelperBlock` `Flatten` test.
#553
- Allocate Exceptions in the ReadStart callbacks if necessary instead
of in UvStreamHandle.
- This also fixes a bug in ListenerSecondary where it should have
previously been looking at the error code instead of the read count.
#237
This change rewrites simple and safe Expression<Func<T, U>> expressions
into accesses to readonly fields. This allows us to cache the actual
expression and avoid repeatedly allocating and compiling it.
The rewrite is limited to cases where we know that the expression doesn't
capture, and where we support that kind of expression for evaluating
viewdata. In practice this means 'indentity' and property accessors are
allowed.