In order to keep the bazel bin directory as clean as possible, we should not write definition files that are not relevant to a `ng_package` to an undesired location in the bazel bin directory. This currently just happens because we only filter out external definition files while we also should filter out definitions that aren't just in the current package.
The `packager.ts` file currently tries to write these files to the package, but fails because those are not inside of the current package. So the logic to create a relative path for the file fails, and the definition will be copied to a location like:
```js
// Notice the double "bazel-out" here.
C:\Users\Paul\_bazel_Paul\kn4tsvyh\execroot\angular_material\bazel-out\x64_windows-fastbuild\bin\src\bazel-out\x64_windows-fastbuild\bin\src\cdk
```
[See logic that causes this](4f9374951d/packages/bazel/src/ng_package/packager.ts (L105-L124)) (nothing wrong with that logic because it assumes that only paths from within the package are passed to it)
PR Close#27519
44dfa606ed