Some test cases incorrectly rely on the side effect of other test cases
importing `NgMatchers`. This commit fixes this by making `expect` in
`core/testing_internal` properly typed.
BREAKING CHANGES:
"{" is used a a delimiter for ICU messages then it could not be used in text nodes.
"{" should be escaped as "{{ '{' }}"
Before:
<span>some { valid } text</span>
After:
<span>some { invalid } text<span> <!-- throw parse error -->
<span>some {{ '{' }} valid } text</span>
BREAKING CHANGE:
`ComponentFixture` will be moving out of `@angular/compiler/testing` to `@angular/core/testing` in
this release. For now, it is deprecated from `@angular/compiler/testing`.