Add month and year to time_format.

ui/strings/ui_strings.grd

 <?xml version="1.0" encoding="UTF-8"?>
 
 <!-- This file contains definitions of resources that will be translated for
 each locale. Specifically, these are UI strings that are used by app/ that
 need to be translated for each locale.-->
 
 <grit base_dir="." latest_public_release="0" current_release="1"
       output_all_resource_defines="false" source_lang_id="en" enc_check="möl">
   <outputs>
     <!-- TODO add each of your output files.  Modify the three below, and add
@@ skipping 189 matching lines @@
                desc="[ICU Syntax]">
                {DAYS, plural, =1 {1 day} other {# days}}
       </message>
 
 
       <message name="IDS_TIME_DAYS_1ST"
                desc="First part of 'xx days and yy hours' time format (including 'and' and the space between first and second part, if the language requires a connecting word like 'and' and a space there). [ICU Syntax]">
                {DAYS, plural, =1 {1 day and } other {# days and }}
       </message>
 
+      <message name="IDS_TIME_MONTHS"
+               desc="[ICU Syntax]">
+               {MONTGS, plural, =1 {1 month} other {# months}}

[jungshik at Google, 2017/04/11 19:01:32]

nit: MONTHS instead of MONTGS

+      </message>
+
+      <message name="IDS_TIME_YEARS"
+               desc="[ICU Syntax]">
+               {YEARS, plural, =1 {1 year} other {# years}}
+      </message>
+
       <message name="IDS_TIME_REMAINING_SECS"
                desc="Seconds remaining for a job completion. Use an abbreviated word for second(s). [ICU Syntax]">
                {SECONDS, plural, =1 {1 sec left} other {# secs left}}
       </message>
 
       <message name="IDS_TIME_REMAINING_LONG_SECS"
                desc="Seconds remaining for a job completion. [ICU Syntax]">
                {SECONDS, plural, =1 {1 second left} other {# seconds left}}
       </message>
 
@@ skipping 10 matching lines @@
       <message name="IDS_TIME_REMAINING_HOURS"
                desc="Hours remaining for a job completition. [ICU Syntax]">
                {HOURS, plural, =1 {1 hour left} other {# hours left}}
       </message>
 
       <message name="IDS_TIME_REMAINING_DAYS"
                desc="Days remaining for a job completion. [ICU Syntax]">
                {DAYS, plural, =1 {1 day left} other {# days left}}
       </message>
 
+      <message name="IDS_TIME_REMAINING_MONTHS"
+               desc="Months remaining for a job completion. [ICU Syntax]">
+               {MONTHS, plural, =1 {1 month left} other {# months left}}
+      </message>
+
+      <message name="IDS_TIME_REMAINING_YEARS"
+               desc="Years remaining for a job completion. [ICU Syntax]">
+               {YEARS, plural, =1 {1 year left} other {# years left}}
+      </message>
+
       <message name="IDS_TIME_ELAPSED_SECS"
                desc="Relative time in browsing history or file list. Use an abbreviated word for second(s). [ICU Syntax]">
                {SECONDS, plural, =1 {1 sec ago} other {# secs ago}}
       </message>
 
       <message name="IDS_TIME_ELAPSED_LONG_SECS"
                desc="Relative time in browsing history or file list. [ICU Syntax]">
                {SECONDS, plural, =1 {1 second ago} other {# seconds ago}}
       </message>
 
@@ skipping 10 matching lines @@
       <message name="IDS_TIME_ELAPSED_HOURS"
                desc="Relative time in browsing history or file list. [ICU Syntax]">
                {HOURS, plural, =1 {1 hour ago} other {# hours ago}}
       </message>
 
       <message name="IDS_TIME_ELAPSED_DAYS"
                desc="Relative time in browsing history or file list. [ICU Syntax]">
                {DAYS, plural, =1 {1 day ago} other {# days ago}}
       </message>
 
+      <message name="IDS_TIME_ELAPSED_MONTHS"
+               desc="Relative time in browsing history or file list. [ICU Syntax]">
+               {MONTHS, plural, =1 {1 month ago} other {# months ago}}
+      </message>
+
+      <message name="IDS_TIME_ELAPSED_YEARS"
+               desc="Relative time in browsing history or file list. [ICU Syntax]">
+               {YEARS, plural, =1 {1 year ago} other {# years ago}}
+      </message>
+
       <message name="IDS_PAST_TIME_TODAY" desc="Relative day today">
         Today
       </message>
       <message name="IDS_PAST_TIME_YESTERDAY" desc="Relative day yesterday">
         Yesterday
       </message>
 
       <!-- Menus -->
       <message name="IDS_APP_MENU_EMPTY_SUBMENU" desc="Used when a submenu has no entries">
         (empty)
@@ skipping 410 matching lines @@
       </message>
       <message name="IDS_DISPLAY_NAME_INTERNAL" desc="The name used for internal displays, which is shown in the display settings.">
         Internal Display
       </message>
       <message name="IDS_DISPLAY_NAME_VIRTUAL" desc="The name used for virtual displays, which is shown in the display settings. Virtual displays are not associated with a physical monitor.">
         Virtual Display
       </message>
     </messages>
   </release>
 </grit>