[clang-format] Fix PR30527: Regression when clang-format insert spaces in [] when...

[clang-format] Fix PR30527: Regression when clang-format insert spaces in [] when in template

Actual regression was introduced in r272668. This revision fixes JS script, but
also regress Cpp case. It manifests with spaces added when template is followed
with array. Bug 30527 mentions case of array as a nested template type
(foo<bar<baz>[]>). Fix is to detect such case and to prevent treating it as
array initialization, but as a subscript case. However, before r272668, this
case was treated simple because we were detecting it as a StartsObjCMethodExpr.
Same was true for other similar case - array of templates (foo<int>[]). This
patch tries to address two problems: 1) fixing regression 2) making sure both
cases (array as a nested type, array of templates) which were entering
StartsObjCMethodExpr branch are handled now appropriately.

https://reviews.llvm.org/D26163
Patch from Branko Kokanovic <branko@kokanovic.org>!

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@286507 91177308-0d34-0410-b5e6-96231b3b80d8