Enable Safe Browsing download protection on Fuchsia

This CL makes a couple changes to how file type policies are controlled
to support building Chrome for Fuchsia.
1. We disable the File Type Policies component updater, since we can't
get a Fuchsia-specific version of the component.
2. We ship a minimal file type policy with all file types marked as
safe.

This effectively disables download protection without disabling other
Safe Browsing functionality. If Fuchsia is ever in need of download
protection, we can fairly easily modify this approach to ship a
different file type policy in the future.

Bug: 1056278
Change-Id: I835fcb70ea1bed63193be830f53ed57a9ea2d3a7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3012281
Reviewed-by: Nathan Parker <[email protected]>
Reviewed-by: David Dorwin <[email protected]>
Reviewed-by: Wez <[email protected]>
Reviewed-by: Sorin Jianu <[email protected]>
Reviewed-by: Bettina Dea <[email protected]>
Commit-Queue: Daniel Rubery <[email protected]>
Cr-Commit-Position: refs/heads/master@{#900579}
diff --git a/chrome/browser/BUILD.gn b/chrome/browser/BUILD.gn
index 25d393b..a56aa5a 100644
--- a/chrome/browser/BUILD.gn
+++ b/chrome/browser/BUILD.gn
@@ -318,8 +318,6 @@
     "component_updater/crl_set_component_installer.h",
     "component_updater/crowd_deny_component_installer.cc",
     "component_updater/crowd_deny_component_installer.h",
-    "component_updater/file_type_policies_component_installer.cc",
-    "component_updater/file_type_policies_component_installer.h",
     "component_updater/first_party_sets_component_installer.cc",
     "component_updater/first_party_sets_component_installer.h",
     "component_updater/floc_component_installer.cc",
@@ -6657,6 +6655,13 @@
       "//components/safe_browsing/content/common/proto:download_file_types_proto",
     ]
   }
+
+  if (!is_fuchsia) {
+    sources += [
+      "component_updater/file_type_policies_component_installer.cc",
+      "component_updater/file_type_policies_component_installer.h",
+    ]
+  }
 }
 
 if (is_android) {