Code: void RecordResourceCompletionUMA(bool image_complete,
                                 bool css_complete,
                                 bool xhr_complete) {
  base::UmaHistogramBoolean("OfflinePages.Background.ResourceCompletion.Image",
                            image_complete);
  base::UmaHistogramBoolean("OfflinePages.Background.ResourceCompletion.Css",
                            css_complete);
  base::UmaHistogramBoolean("OfflinePages.Background.ResourceCompletion.Xhr",
                            xhr_complete);
}

Vulnerability Type: Overflow 
CWE ID: CWE-119
Summary: Heap buffer overflow during image processing in Skia in Google Chrome prior to 56.0.2924.76 for Linux, Windows and Mac, and 56.0.2924.87 for Android, allowed a remote attacker to perform an out of bounds memory read via a crafted HTML page.
Commit Message: Remove unused histograms from the background loader offliner.

Bug: 975512
Change-Id: I87b0a91bed60e3a9e8a1fd9ae9b18cac27a0859f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1683361
Reviewed-by: Cathy Li <chili@chromium.org>
Reviewed-by: Steven Holte <holte@chromium.org>
Commit-Queue: Peter Williamson <petewil@chromium.org>
Cr-Commit-Position: refs/heads/master@{#675332}