Remove all the ephemeral apps code.

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 389e013988dc30e7616528d62959cc9b5d4902f1..6224289067787bd1f5528657ce1c25b94e1f4e0f 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -60524,7 +60524,7 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   <int value="6" label="ERROR_ON_PRIVATE_KEY"/>
   <int value="7" label="WAS_INSTALLED_BY_DEFAULT"/>
   <int value="8" label="REQUIRE_PERMISSIONS_CONSENT"/>
-  <int value="9" label="IS_EPHEMERAL"/>
+  <int value="9" label="IS_EPHEMERAL_UNUSED"/>
   <int value="10" label="WAS_INSTALLED_BY_OEM"/>
 </enum>
 
@@ -60548,7 +60548,7 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   <int value="512" label="GREYLIST"/>
   <int value="1024" label="CORRUPTED"/>
   <int value="2048" label="REMOTE_INSTALL"/>
-  <int value="4096" label="INACTIVE_EPHEMERAL_APP"/>
+  <int value="4096" label="INACTIVE_EPHEMERAL_APP_UNUSED"/>

[Devlin, 2015/12/07 16:53:59]

ditto

[benwells, 2015/12/08 07:20:11]

Done.

   <int value="8192" label="EXTERNAL_EXTENSION"/>
   <int value="16384" label="UPDATE_REQUIRED_BY_POLICY"/>
 </enum>