Add UI for the new harmful download warning

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 96f84dfbc4771674bdd54d4a1a4cd39369c16b5b..0ffc1e9d2f49e00fe5a08366fd779934d569b21b 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -10453,6 +10453,22 @@ Therefore, the affected-histogram name has to have at least one dot in it.
   </summary>
 </histogram>
 
+<histogram name="interstitial.harmful.decision" enum="SB3InterstitialDecision">
+  <owner>felt@chromium.org</owner>
+  <summary>
+    User decision when presented with a Safe Browsing harmful program
+    interstitial.
+  </summary>
+</histogram>
+
+<histogram name="interstitial.harmful.interaction"
+    enum="SB3InterstitialInteraction">
+  <owner>felt@chromium.org</owner>
+  <summary>
+    User interactions with a Safe Browsing harmful download interstitial.

[mattm, 2014/09/19 21:28:16]

use same language in both? ("harmful program interstitial" vs "harmful download
interstitial")

[felt, 2014/09/22 16:42:16]

Done.

+  </summary>
+</histogram>
+
 <histogram name="interstitial.malware.decision" enum="SB3InterstitialDecision">
   <owner>felt@chromium.org</owner>
   <summary>