feat: enable pdf viewer (#21794)

shell/browser/extensions/api/BUILD.gn

@@ -0,0 +1,35 @@
+# Copyright 2018 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import("//extensions/buildflags/buildflags.gni")
+import("//tools/json_schema_compiler/json_schema_api.gni")
+
+assert(enable_extensions,
+       "Cannot depend on extensions because enable_extensions=false.")
+
+function_registration("api_registration") {
+  sources = [
+    "//electron/shell/common/extensions/api/extension.json",
+    "//electron/shell/common/extensions/api/resources_private.idl",
+    "//electron/shell/common/extensions/api/tabs.json",
+  ]
+  impl_dir = "//electron/shell/browser/extensions/api"
+  configs = [ "//build/config:precompiled_headers" ]
+  bundle_name = "Electron"
+  root_namespace = "extensions::api::%(namespace)s"
+  schema_include_rules = "extensions/common/api:extensions::api::%(namespace)s"
+
+  deps = [
+    # Different APIs include headers from these targets.
+    "//components/zoom",
+    "//content/public/browser",
+    "//extensions/browser",
+
+    # Different APIs include some headers from chrome/common that in turn
+    # include generated headers from these targets.
+    # TODO(brettw) this should be made unnecessary if possible.
+    "//electron/shell/common/extensions/api",
+  ]
+  deps += [ "//extensions/common/api" ]
+}