adb: allow filtering by file in coverage/show.sh.

Test: ./coverage.sh transport.cpp
Change-Id: I5fd3b25d9b3edd7a9131dae902e1868ced0384cc
diff --git a/adb/coverage/show.sh b/adb/coverage/show.sh
index 7ea7949..3b2faa3 100755
--- a/adb/coverage/show.sh
+++ b/adb/coverage/show.sh
@@ -5,8 +5,18 @@
 OUTPUT_DIR=$(realpath $(dirname "$0"))
 . "$OUTPUT_DIR"/include.sh
 
+BASE_PATH=/proc/self/cwd/system/core/adb
+PATHS=""
+if [[ $# == 0 ]]; then
+  PATHS=$BASE_PATH
+else
+  for arg in "$@"; do
+    PATHS="$PATHS $BASE_PATH/$arg"
+  done
+fi
+
 cd $ANDROID_BUILD_TOP
 llvm-cov show --instr-profile="$OUTPUT_DIR"/adbd.profdata \
   $ANDROID_PRODUCT_OUT/apex/com.android.adbd/bin/adbd \
-  /proc/self/cwd/system/core/adb \
+  $PATHS \
   $ADB_TEST_BINARIES