Since IE11 does not support `Function#name`, we use a shim in tests that
parses the stringified function to extract the name. Previously, that
shim would cache the computed name on the function to speed up future
invocations. However, this resulted in incorrect values for functions
that "extended" other functions (such as the code generated by
TypeScript when downleveling ES2015 classes that extended other
classes).
To avoid issues such as #41416 (see also [internal discussion][1]), this
commit removes the caching of names. This is not expected to noticeably
affect performance, since (a) it is only used in tests, (b) it is only
used on browsers that do not natively support `Function#name` (i.e.
IE11) and (c) accessing function names is rare and inexpensive compared
to other operations that happen during testing.
[1]: https://angular-team.slack.com/archives/CB4UC1932/p1617285258058000
PR Close#41439
This commit removes polyfills that were needed to run tests on IE 9 and IE 10.
BREAKING CHANGE:
In v10, IE 9, 10, and IE mobile support was deprecated. In v11, Angular framework removes IE 9,
10, and IE mobile support completely.
Supporting outdated browsers like these increases bundle size, code complexity, and test load,
and also requires time and effort that could be spent on improvements to the framework.
For example, fixing issues can be more difficult, as a straightforward fix for modern browsers
could break old ones that have quirks due to not receiving updates from vendors.
PR Close#38931
The shims_for_IE.js file contains vendor code that predates the third_party
directory. This file is currently used for internal karma testing setup. This
change corrects this by moving the shims_for_IE file to //third_part/
PR Close#37624
George Kalpakas
Marcono1234
Andrew Kushnir
Joey Perrott