Merge to XFA: Pull in gmock for standalone pdfium builds.

BUILD.gn

Index: BUILD.gn
diff --git a/BUILD.gn b/BUILD.gn
index 1e7f162bf38c9ff4e07b9b7afdacf89eeb2bb37c..4e143c8bef03a83fad00e709085f5776a3532f8d 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -1574,14 +1574,17 @@ test("pdfium_embeddertests") {
   sources = [
     "fpdfsdk/src/fpdf_dataavail_embeddertest.cpp",
     "fpdfsdk/src/fpdfdoc_embeddertest.cpp",
+    "fpdfsdk/src/fpdfformfill_embeddertest.cpp",
     "fpdfsdk/src/fpdftext_embeddertest.cpp",
     "fpdfsdk/src/fpdfview_embeddertest.cpp",
     "testing/embedder_test.cpp",
     "testing/embedder_test.h",
+    "testing/embedder_test_mock_delegate.h",
     "testing/fx_string_testhelpers.cpp",
     "testing/fx_string_testhelpers.h",
   ]
   deps = [
+    "//testing/gmock",
     "//testing/gtest",
     ":pdfium"
   ]