Add support for converting I420 software frames into NV12 hardware frames

cc/test/test_gpu_memory_buffer_manager.cc

Index: cc/test/test_gpu_memory_buffer_manager.cc
diff --git a/cc/test/test_gpu_memory_buffer_manager.cc b/cc/test/test_gpu_memory_buffer_manager.cc
index f8bec8ed38d6852b8fa3f463b88af31a1bab732f..0237a4c1e52c99398622acb804fc8d246afa9a2c 100644
--- a/cc/test/test_gpu_memory_buffer_manager.cc
+++ b/cc/test/test_gpu_memory_buffer_manager.cc
@@ -31,6 +31,11 @@ size_t SubsamplingFactor(gfx::BufferFormat format, int plane) {
       DCHECK_LT(static_cast<size_t>(plane), arraysize(factor));
       return factor[plane];
     }
+    case gfx::BufferFormat::YUV_420_BIPLANAR: {
+      static size_t factor[] = {1, 2};
+      DCHECK_LT(static_cast<size_t>(plane), arraysize(factor));
+      return factor[plane];
+    }
   }
   NOTREACHED();
   return 0;
@@ -61,6 +66,8 @@ size_t StrideInBytes(size_t width, gfx::BufferFormat format, int plane) {
       return width * 4;
     case gfx::BufferFormat::YUV_420:
       return width / SubsamplingFactor(format, plane);
+    case gfx::BufferFormat::YUV_420_BIPLANAR:
+      return width;
   }
   NOTREACHED();
   return 0;