Update trim_data to deal with locale fallback failure for unit

scripts/trim_data.sh

Index: scripts/trim_data.sh
diff --git a/scripts/trim_data.sh b/scripts/trim_data.sh
index 46be26c88ac527ef549d81c4069df15142b92a12..a60bd46bd89faeb57554015cea7a9317da249a3f 100755
--- a/scripts/trim_data.sh
+++ b/scripts/trim_data.sh
@@ -3,6 +3,7 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
+set -e
 
 # Remove entries currently not used in Chromium/V8.
 function filter_locale_data {
@@ -184,6 +185,14 @@ function filter_unit_data {
          /^    \}$/ p
          d
        }' ${i}
+
+    # Delete empty units,units{Narrow|Short} block. Otherwise, locale fallback
+    # fails. See crbug.com/707515.
+    sed -r -i \
+      '/^    units(|Narrow|Short)\{$/ {
+         N
+         /^    units(|Narrow|Short)\{\n    \}/ d

[Daniel Erat, 2017/04/11 21:18:10]

sorry, my sed is a bit rusty/nonexistent. i think that this line is deleting
opening units lines followed by closing units lines, but i'm not sure what the
earlier pattern or the 'N' ("Read/append the next line of input into the pattern
space.") does. can you explain it for me?

[jungshik at Google, 2017/04/11 21:53:17]

    unitsNarrow{
    }

Given an input like the above, 

this line will match the first input line above and add it to the pattern space.

 
'/^    units(|Narrow|Short)\{$/ {

"N" will append the next input line ("    }") to the pattern space, making it
read like 
    unitsNarrow{\n    \}

Then, " /^    units(|Narrow|Short)\{\n    \}/" will match the pattern space and
will delete it starting a new cycle (processing the next input line. 

If the regex is not matched, the pattern space is just printed out and sed will
move on to process the next input line.

See  http://www.grymoire.com/Unix/Sed.html#uh-51 that I found after writing the
above. :-) 

+      }' ${i}
   done
 }