Consolidate test support code.

pdfium.gyp

 {
   'variables': {
     'pdf_use_skia%': 0,
     'pdf_enable_v8%': 1,
     'conditions': [
       ['OS=="linux"', {
         'bundle_freetype%': 0,
       }, {  # On Android there's no system FreeType. On Windows and Mac, only a
             # few methods are used from it.
         'bundle_freetype%': 1,
@@ skipping 746 matching lines @@
         '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',
+        'testing/test_support.cpp',
+        'testing/test_support.h',
       ],
       'conditions': [
         ['pdf_enable_v8==1', {
           'include_dirs': [
             '<(DEPTH)/v8',
             '<(DEPTH)/v8/include',
           ],
           'dependencies': [
             '<(DEPTH)/v8/tools/gyp/v8.gyp:v8',
             '<(DEPTH)/v8/tools/gyp/v8.gyp:v8_libplatform',
           ],
           'sources': [
             'fpdfsdk/src/jsapi/fxjs_v8_embeddertest.cpp',
           ],
         }],
       ],
     },
   ],
 }