Restore TEST_MAPPING files removed during repackaging

Running a script like external/conscrypt/srcgen/generate_android_src.sh
removed the TEST_MAPPING files. This change restores them by checking
them out of git. This does mean that if a TEST_MAPPING file has been
edited that the changes will be lost.

Test: external/conscrypt/srcgen/generate_android_src.sh
Change-Id: Ifedff3823f14a7a098a677709bf1ce89b5a8c22d
diff --git a/scripts/repackage-common.sh b/scripts/repackage-common.sh
index 23985b2..94af157 100644
--- a/scripts/repackage-common.sh
+++ b/scripts/repackage-common.sh
@@ -163,6 +163,9 @@
        --target-dir ${SRC_OUT_DIR} \
        --change-log ${CHANGE_LOG} \
        ${REPACKAGE_ARGS}
+
+  # Restore TEST_MAPPING files that may have been removed from the source directory
+  (cd $SRC_OUT_DIR; git checkout HEAD $(git status --short | grep -E "^ D .*/TEST_MAPPING$" | cut -c4-))
 }
 
 REPACKAGED_DIR=${PROJECT_DIR}/repackaged