Add htm and html to pingable download file types.

BUG=719784
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:closure_compilation

Review-Url: https://codereview.chromium.org/2866223002
Cr-Commit-Position: refs/heads/master@{#470514}
diff --git a/chrome/browser/resources/safe_browsing/README.md b/chrome/browser/resources/safe_browsing/README.md
index c745b96..15916e4 100644
--- a/chrome/browser/resources/safe_browsing/README.md
+++ b/chrome/browser/resources/safe_browsing/README.md
@@ -10,7 +10,7 @@
 
 
 ## Procedure for adding/modifying file type(s)
-  * **Edit** `download_file_types.asciipb` and update `histograms.xml`
+  * **Edit** `download_file_types.asciipb` and update `enums.xml`
   * Get it reviewed, **submit.**
   * **Push** it to all users via component update:
     * Wait 1-3 day for this to run on Canary to verify it doesn't crash Chrome.
@@ -34,7 +34,7 @@
     first one wins. Only the `default_file_type` should leave this unset.
 
   * `uma_value`: (required) must be unique and match one in the
-    `SBClientDownloadExtensions` enum in `histograms.xml`.
+    `SBClientDownloadExtensions` enum in `enums.xml`.
 
   * `is_archive`: `True` if this filetype is a container for other files.
      Leave it unset for `false`.
diff --git a/chrome/browser/resources/safe_browsing/download_file_types.asciipb b/chrome/browser/resources/safe_browsing/download_file_types.asciipb
index 6641e0d..a61c0826 100644
--- a/chrome/browser/resources/safe_browsing/download_file_types.asciipb
+++ b/chrome/browser/resources/safe_browsing/download_file_types.asciipb
@@ -8,7 +8,7 @@
 ##
 ## Top level settings
 ##
-version_id: 9
+version_id: 10
 sampled_ping_probability: 0.01
 default_file_type {
   uma_value: 18
@@ -1809,6 +1809,28 @@
   }
 }
 file_types {
+  # HTML file. This extension is abused by UwS campaigns to evade referrer
+  # attribution via a two-level download scheme. crbug.com/719784
+  extension: "htm"
+  uma_value: 284
+  ping_setting: FULL_PING
+  platform_settings {
+    danger_level: NOT_DANGEROUS
+    auto_open_hint: ALLOW_AUTO_OPEN
+  }
+}
+file_types {
+  # HTML file. This extension is abused by UwS campaigns to evade referrer
+  # attribution via a two-level download scheme. crbug.com/719784
+  extension: "html"
+  uma_value: 285
+  ping_setting: FULL_PING
+  platform_settings {
+    danger_level: NOT_DANGEROUS
+    auto_open_hint: ALLOW_AUTO_OPEN
+  }
+}
+file_types {
   # Hypertext Template File. See https://support.microsoft.com/kb/181689.
   extension: "htt"
   uma_value: 79