Consolidate test support code.

BUILD.gn

 # Copyright 2014 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("//testing/test.gni")
 import("pdfium.gni")
 
 config("pdfium_config") {
   cflags = []
   include_dirs = [ "third_party/freetype/include" ]
@@ skipping 115 matching lines @@
     ]
   }
 
   if (pdfium_bundle_freetype) {
     deps += [ "third_party:fx_freetype" ]
   } else {
     libs += [ "freetype" ]
   }
 }
 
+source_set("test_support") {
+  testonly = true
+  sources = [
+    "testing/fx_string_testhelpers.cpp",
+    "testing/fx_string_testhelpers.h",
+    "testing/test_support.cpp",
+    "testing/test_support.h",
+  ]
+  deps = [
+    "//testing/gmock",
+    "//testing/gtest",
+    ":pdfium",
+  ]
+  include_dirs = [
+    "."
+  ]
+  if (pdf_enable_v8) {
+    deps += [
+      "//v8",
+      "//v8:v8_libplatform",
+    ]
+    include_dirs += [
+      "//v8",
+      "//v8/include",
+    ]
+  }
+  configs -= [ "//build/config/compiler:chromium_code" ]
+  configs += [
+    ":pdfium_config",
+    "//build/config/compiler:no_chromium_code",
+  ]
+}
+
 # Targets below this are only visible within this file (and to the
 # top-level gn_visibility target used to help gn_all build everything).
 visibility = [
   ":*",
   "//:gn_visibility",
 ]
 
 static_library("fdrm") {
   sources = [
     "core/include/fdrm/fx_crypt.h",
@@ skipping 578 matching lines @@
 }
 
 test("pdfium_unittests") {
   sources = [
     "core/src/fxcodec/codec/fx_codec_jpx_unittest.cpp",
     "core/src/fxcrt/fx_basic_bstring_unittest.cpp",
     "core/src/fxcrt/fx_basic_memmgr_unittest.cpp",
     "core/src/fxcrt/fx_basic_wstring_unittest.cpp",
     "core/src/fxcrt/fx_bidi_unittest.cpp",
     "core/src/fxcrt/fx_system_unittest.cpp",
-    "testing/fx_string_testhelpers.cpp",
-    "testing/fx_string_testhelpers.h",
     "third_party/base/nonstd_unique_ptr_unittest.cpp",
   ]
   deps = [
     "//testing/gtest",
     "//testing/gtest:gtest_main",
     ":pdfium",
+    ":test_support",
   ]
   include_dirs = [ "." ]
   configs -= [ "//build/config/compiler:chromium_code" ]
   configs += [
     ":pdfium_config",
     "//build/config/compiler:no_chromium_code",
   ]
 }
 
 test("pdfium_embeddertests") {
   sources = [
     "core/src/fpdfapi/fpdf_parser/fpdf_parser_decode_embeddertest.cpp",
     "core/src/fpdfapi/fpdf_parser/fpdf_parser_parser_embeddertest.cpp",
     "fpdfsdk/src/fpdf_dataavail_embeddertest.cpp",
     "fpdfsdk/src/fpdfdoc_embeddertest.cpp",
     "fpdfsdk/src/fpdfformfill_embeddertest.cpp",
     "fpdfsdk/src/fpdftext_embeddertest.cpp",
     "fpdfsdk/src/fpdfview_c_api_test.c",
     "fpdfsdk/src/fpdfview_c_api_test.h",
     "fpdfsdk/src/fpdfview_embeddertest.cpp",
     "testing/embedder_test.cpp",
     "testing/embedder_test.h",
     "testing/embedder_test_mock_delegate.h",
     "testing/embedder_test_timer_handling_delegate.h",
-    "testing/fx_string_testhelpers.cpp",
-    "testing/fx_string_testhelpers.h",
   ]
   deps = [
     "//testing/gmock",
     "//testing/gtest",
     ":pdfium",
+    ":test_support",
   ]
   include_dirs = [
     "."
   ]
   if (pdf_enable_v8) {
     sources += [
      "fpdfsdk/src/jsapi/fxjs_v8_embeddertest.cpp"
     ]
     deps += [
       "//v8",
       "//v8:v8_libplatform",
     ]
     include_dirs += [
       "//v8",
       "//v8/include",
     ]
   }
   configs -= [ "//build/config/compiler:chromium_code" ]
   configs += [
     ":pdfium_config",
     "//build/config/compiler:no_chromium_code",
   ]
 }