Revert r342183 "[DAGCombine] Fix crash when store merging created an extract_subvector with invalid index."

Causes 'isVector() && "Invalid vector type!"' assertion when building
Skia in Chrome.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@342265 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed