GM: add --missingExpectationsPath option, similar to --mismatchPath

gm/tests/run.sh

 #!/bin/bash
 
 # Self-tests for gm, based on tools/tests/run.sh
 #
 # These tests are run by the Skia_PerCommit_House_Keeping bot at every commit,
 # so make sure that they still pass when you make changes to gm!
 #
 # To generate new baselines when gm behavior changes, run gm/tests/rebaseline.sh
 #
 # TODO: because this is written as a shell script (instead of, say, Python)
@@ skipping 90 matching lines @@
   grep ^GM: $ACTUAL_OUTPUT_DIR/stderr >$ACTUAL_OUTPUT_DIR/stderr-tmp
   mv $ACTUAL_OUTPUT_DIR/stderr-tmp $ACTUAL_OUTPUT_DIR/stderr
 
   # Replace image file contents with just the filename, for two reasons:
   # 1. Image file encoding may vary by platform
   # 2. https://code.google.com/p/chromium/issues/detail?id=169600
   #    ('gcl/upload.py fail to upload binary files to rietveld')
   for IMAGEFILE in $(find $ACTUAL_OUTPUT_DIR -name *.png); do
     echo "[contents of $IMAGEFILE]" >$IMAGEFILE
   done
-  if [ -d $ACTUAL_OUTPUT_DIR/mismatchPath ]; then
-    for MISMATCHDIR in $(find $ACTUAL_OUTPUT_DIR/mismatchPath -mindepth 1 -type d); do
-      echo "Created additional file to make sure directory isn't empty, because self-test cannot handle empty directories." >$MISMATCHDIR/bogusfile
-    done
-  fi
+
+  # Add a file to any empty subdirectories.

[epoger, 2013/06/21 17:39:42]

Patchset 1 fixes the way we prevent empty subdirectories from being written.  No
changes to the GM binary yet, just the self-test.

+  for DIR in $(find $ACTUAL_OUTPUT_DIR -mindepth 1 -type d); do
+    echo "Created additional file to make sure directory isn't empty, because self-test cannot handle empty directories." >$DIR/bogusfile
+  done
 
   compare_directories $EXPECTED_OUTPUT_DIR $ACTUAL_OUTPUT_DIR
 }
 
 # Create input dir (at path $1) with expectations (both image and json)
 # that gm will match or mismatch as appropriate.
 #
 # We used to check these files into SVN, but then we needed to rebaseline them
 # when our drawing changed at all... so, as proposed in
 # http://code.google.com/p/skia/issues/detail?id=1068 , we generate them
@@ skipping 103 matching lines @@
 for CASE in $FAILING_CASES; do
   assert_fails "python gm/display_json_results.py $GM_OUTPUTS/$CASE/$OUTPUT_EXPECTED_SUBDIR/json-summary.txt"
 done
 
 if [ $ENCOUNTERED_ANY_ERRORS == 0 ]; then
   echo "All tests passed."
   exit 0
 else
   exit 1
 fi