Verify the "pdf-form-save" is enabled in the saveData_() JS handler.

Aside from adding the sanity check, this also hooks up loadTimeData in
pdf_viewer.js, and demonstrates how to plumb a feature flag from the
browser into pdf_viewer.js.

BUG=61248

Change-Id: I48850afaac17854af785d04a8ca93078ebd8532f
Reviewed-on: https://chromium-review.googlesource.com/c/1339244Reviewed-by: Demetrios Papadopoulos <dpapad@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
Cr-Commit-Position: refs/heads/master@{#608890}

chrome/browser/extensions/BUILD.gn

@@ -9,6 +9,7 @@ import("//chrome/common/features.gni")
 import("//components/nacl/features.gni")
 import("//extensions/buildflags/buildflags.gni")
 import("//mojo/public/tools/bindings/mojom.gni")
+import("//pdf/features.gni")
 import("//rlz/buildflags/buildflags.gni")
 
 assert(enable_extensions)
@@ -1102,6 +1103,13 @@ jumbo_static_library("extensions") {
     ]
   }
 
+  if (enable_pdf) {
+    deps += [
+      "//pdf:buildflags",
+      "//pdf:features",
+    ]
+  }
+
   if (enable_rlz_support) {
     deps += [ "//rlz:rlz_lib" ]
   }

chrome/browser/extensions/api/resources_private/resources_private_api.cc

@@ -12,9 +12,14 @@
 #include "chrome/common/extensions/api/resources_private.h"
 #include "chrome/grit/generated_resources.h"
 #include "components/strings/grit/components_strings.h"
+#include "pdf/buildflags.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/base/webui/web_ui_util.h"
 
+#if BUILDFLAG(ENABLE_PDF)
+#include "pdf/pdf_features.h"
+#endif
+
 // To add a new component to this API, simply:
 // 1. Add your component to the Component enum in
 //      chrome/common/extensions/api/resources_private.idl
@@ -54,6 +59,14 @@ void AddStringsForPdf(base::DictionaryValue* dict) {
   SetL10nString(dict, "tooltipZoomOut", IDS_PDF_TOOLTIP_ZOOM_OUT);
 }
 
+void AddAdditionalDataForPdf(base::DictionaryValue* dict) {
+#if BUILDFLAG(ENABLE_PDF)
+  dict->SetKey("pdfFormSaveEnabled",
+               base::Value(base::FeatureList::IsEnabled(
+                   chrome_pdf::features::kSaveEditedPDFForm)));
+#endif
+}
+
 }  // namespace
 
 namespace get_strings = api::resources_private::GetStrings;
@@ -65,7 +78,7 @@ ResourcesPrivateGetStringsFunction::~ResourcesPrivateGetStringsFunction() {}
 ExtensionFunction::ResponseAction ResourcesPrivateGetStringsFunction::Run() {
   std::unique_ptr<get_strings::Params> params(
       get_strings::Params::Create(*args_));
-  std::unique_ptr<base::DictionaryValue> dict(new base::DictionaryValue);
+  auto dict = std::make_unique<base::DictionaryValue>();
 
   api::resources_private::Component component = params->component;
 
@@ -75,6 +88,7 @@ ExtensionFunction::ResponseAction ResourcesPrivateGetStringsFunction::Run() {
       break;
     case api::resources_private::COMPONENT_PDF:
       AddStringsForPdf(dict.get());
+      AddAdditionalDataForPdf(dict.get());
       break;
     case api::resources_private::COMPONENT_NONE:
       NOTREACHED();

chrome/browser/resources/pdf/index.html

@@ -36,6 +36,7 @@
 <script src="zoom_manager.js"></script>
 <script src="gesture_detector.js"></script>
 <script src="pdf_scripting_api.js"></script>
+<script src="chrome://resources/js/load_time_data.js"></script>
 <script src="chrome://resources/js/util.js"></script>
 <script src="browser_api.js"></script>
 <script src="coords_transformer.js"></script>

chrome/browser/resources/pdf/pdf_viewer.js

@@ -652,6 +652,7 @@ PDFViewer.prototype = {
     document.documentElement.dir = strings.textdirection;
     document.documentElement.lang = strings.language;
 
+    loadTimeData.data = strings;
     $('toolbar').strings = strings;
     $('zoom-toolbar').strings = strings;
     $('password-screen').strings = strings;
@@ -798,6 +799,9 @@ PDFViewer.prototype = {
    * @private
    */
   saveData_: function(messageData) {
+    if (!loadTimeData.getBoolean('pdfFormSaveEnabled'))
+      throw new Error('Internal error: save not enabled.');
+
     // Verify a token that was created by this instance is included to avoid
     // being spammed.
     if (!this.pendingTokens_.delete(messageData.token))