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`.