Bug v1.9.3: Spurious whitespace warnings when using git apply with the --exclude option

Bug v1.9.3: Spurious whitespace warnings when using git apply with the --exclude option

REPRO STEPS:
1. Create a patch PATCH that modifies two files, A and B. Make sure the modifications to file A add whitespace errors and the modifications to file B do not.
2. Apply that patch to a repo using git apply PATCH --exclude A

ACTUAL RESULT:
git apply outputs a "warning: n lines add whitespace errors.” where n is the number of lines with whitespace errors in A. 

EXPECTED RESULT:
No warning about adding whitespace errors because no whitespace errors are added to the tree since A is excluded and B has no whitespace errors.