This patch implements a mechanism for more granular link URL permissions (filtering on scheme/host). This fixes the bug that allowed PDFs to have working links to any "chrome://" URLs.

BUG=528505,226927

Review URL: https://codereview.chromium.org/1362433002

Cr-Commit-Position: refs/heads/master@{#351705}
  void GrantPermissionsForFile(ChildProcessSecurityPolicyImpl* p,
                               int child_id,
                               const base::FilePath& file,
                               int permissions) {
    p->GrantPermissionsForFile(child_id, file, permissions);
  }

  void GrantPermissionsForFile(ChildProcessSecurityPolicyImpl* p,
                               int child_id,
                               const base::FilePath& file,
                               int permissions) {
    p->GrantPermissionsForFile(child_id, file, permissions);
  }
