Fixing/disabling Windows x64 warnings

Disabled MSVC #4267 warnings in common.gypi to enable x64 builds
for Windows.
Fixed MSVC #4267 warnings in test/testsupport.
Added third_party/directxsdk to .gitignore.

With http://review.webrtc.org/1070008 landed, this should make it possible
to build for x64 on Windows.

BUG=1348
TEST=Compiling with http://review.webrtc.org/1070008 applied:
set GYP_DEFINES="target_arch=x64"
set GYP_GENERATORS=ninja
gclient sync
ninja -C out\Debug_x64

Review URL: https://webrtc-codereview.appspot.com/1060008

git-svn-id: http://webrtc.googlecode.com/svn/trunk@3464 4adac7df-926f-26a2-2b94-8c16560cd09d

webrtc/modules/video_coding/codecs/tools/video_codecs_tools.gypi

@@ -19,10 +19,14 @@
             '<(DEPTH)/third_party/google-gflags/google-gflags.gyp:google-gflags',
             '<(webrtc_root)/test/metrics.gyp:metrics',
             '<(webrtc_vp8_dir)/vp8.gyp:webrtc_vp8',
-           ],
-           'sources': [
-             'video_quality_measurement.cc',
-           ],
+          ],
+          'sources': [
+            'video_quality_measurement.cc',
+          ],
+          # Disable warnings to enable Win64 build, issue 1323.
+          'msvs_disabled_warnings': [
+            4267,  # size_t to int truncation.
+          ],
         },
       ], # targets
     }], # include_tests

webrtc/modules/video_coding/codecs/vp8/vp8.gyp

@@ -73,6 +73,10 @@
         'include/vp8_common_types.h',
         'vp8_impl.cc',
       ],
+      # Disable warnings to enable Win64 build, issue 1323.
+      'msvs_disabled_warnings': [
+        4267,  # size_t to int truncation.
+      ],
     },
   ], # targets
   'conditions': [

webrtc/modules/video_coding/main/source/video_coding_test.gypi

@@ -93,6 +93,10 @@
         '../../codecs/test/stats_unittest.cc',
         '../../codecs/test/videoprocessor_unittest.cc',
       ],
+      # Disable warnings to enable Win64 build, issue 1323.
+      'msvs_disabled_warnings': [
+        4267,  # size_t to int truncation.
+      ],
     },
   ],
 }