[translate] Add translate ranker model loader.

tools/metrics/histograms/histograms.xml

Index: tools/metrics/histograms/histograms.xml
diff --git a/tools/metrics/histograms/histograms.xml b/tools/metrics/histograms/histograms.xml
index 86869a435ce1fb5ee9a688b389ca56f5a3779b27..da61869d5e47777b8c09b1258a40c4a412fb041b 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -71090,8 +71090,7 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   <summary>Counts translation target page schemes.</summary>
 </histogram>
 
-<histogram name="Translate.Ranker.Model.Status"
-    enum="TranslateRankerModelStatus">
+<histogram name="Translate.Ranker.Model.Status" enum="RankerModelStatus">
   <owner>rogerm@google.com</owner>
   <summary>
     Tracks the outcome of attempts to download a Translate Ranker Model.
@@ -104926,6 +104925,15 @@ value.
   <int value="6" label="In use"/>
 </enum>
 
+<enum name="RankerModelStatus" type="int">
+  <int value="0" label="OK"/>
+  <int value="1" label="Download Throttled"/>
+  <int value="2" label="Download Failed"/>
+  <int value="3" label="Parse Failed"/>
+  <int value="4" label="Validation Failed"/>
+  <int value="5" label="Incompatible"/>
+</enum>
+
 <enum name="RapporDiscardReason" type="int">
   <int value="0" label="Upload Success"/>
   <int value="1" label="Upload Rejected"/>
@@ -109822,14 +109830,6 @@ value.
   <int value="6" label="CLD can complement a sub code"/>
 </enum>
 
-<enum name="TranslateRankerModelStatus" type="int">
-  <int value="0" label="OK"/>
-  <int value="1" label="Download Throttled"/>
-  <int value="2" label="Download Failed"/>
-  <int value="3" label="Parse Failed"/>
-  <int value="4" label="Validation Failed"/>
-</enum>
-
 <enum name="TranslateScheme" type="int">
   <int value="0" label="http"/>
   <int value="1" label="https"/>