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}
ChildProcessSecurityPolicyImpl::ChildProcessSecurityPolicyImpl() {
  RegisterWebSafeScheme(url::kHttpScheme);
  RegisterWebSafeScheme(url::kHttpsScheme);
  RegisterWebSafeScheme(url::kFtpScheme);
  RegisterWebSafeScheme(url::kDataScheme);
  RegisterWebSafeScheme("feed");
  RegisterWebSafeScheme(url::kBlobScheme);
  RegisterWebSafeScheme(url::kFileSystemScheme);

  RegisterPseudoScheme(url::kAboutScheme);
  RegisterPseudoScheme(url::kJavaScriptScheme);
  RegisterPseudoScheme(kViewSourceScheme);
}

ChildProcessSecurityPolicyImpl::ChildProcessSecurityPolicyImpl() {
  RegisterWebSafeScheme(url::kHttpScheme);
  RegisterWebSafeScheme(url::kHttpsScheme);
  RegisterWebSafeScheme(url::kFtpScheme);
  RegisterWebSafeScheme(url::kDataScheme);
  RegisterWebSafeScheme("feed");
  RegisterWebSafeScheme(url::kBlobScheme);
  RegisterWebSafeScheme(url::kFileSystemScheme);

  RegisterPseudoScheme(url::kAboutScheme);
  RegisterPseudoScheme(url::kJavaScriptScheme);
  RegisterPseudoScheme(kViewSourceScheme);
}
