GitLab

HostInstaller uses navigator.platform to figure out which package
needs to be downloaded to install host on the curren machine. Problem
was that on linux navigator.platform may be set to "Linux i686" and
HostIntaller wasn't handling it properly. With this change:
  1. "Linux i686" is properly recognized as ia32 Linux.
  2. Unsupported platforms are properly handled by disabling the
     "Share" button.

BUG=442943

Review URL: https://codereview.chromium.org/874683002

Cr-Commit-Position: refs/heads/master@{#313030}