gpu: Add YCbCr 420v extension.

ui/gl/test/gl_image_test_support.cc

Index: ui/gl/test/gl_image_test_support.cc
diff --git a/ui/gl/test/gl_image_test_support.cc b/ui/gl/test/gl_image_test_support.cc
index 587d13952388c8c89f6b4cfd869d89dd012d348f..4b8f5eb5f5de685e502210ba1695dd563a2db8c1 100644
--- a/ui/gl/test/gl_image_test_support.cc
+++ b/ui/gl/test/gl_image_test_support.cc
@@ -39,11 +39,13 @@ void GLImageTestSupport::CleanupGL() {
 void GLImageTestSupport::SetBufferDataToColor(int width,
                                               int height,
                                               int stride,
+                                              int plane,
                                               BufferFormat format,
                                               const uint8_t color[4],
                                               uint8_t* data) {
   switch (format) {
     case BufferFormat::RGBX_8888:
+      DCHECK_EQ(0, plane);
       for (int y = 0; y < height; ++y) {
         for (int x = 0; x < width; ++x) {
           data[y * stride + x * 4 + 0] = color[0];
@@ -54,6 +56,7 @@ void GLImageTestSupport::SetBufferDataToColor(int width,
       }
       return;
     case BufferFormat::RGBA_8888:
+      DCHECK_EQ(0, plane);
       for (int y = 0; y < height; ++y) {
         for (int x = 0; x < width; ++x) {
           data[y * stride + x * 4 + 0] = color[0];
@@ -64,6 +67,7 @@ void GLImageTestSupport::SetBufferDataToColor(int width,
       }
       return;
     case BufferFormat::BGRX_8888:
+      DCHECK_EQ(0, plane);
       for (int y = 0; y < height; ++y) {
         for (int x = 0; x < width; ++x) {
           data[y * stride + x * 4 + 0] = color[2];
@@ -74,6 +78,7 @@ void GLImageTestSupport::SetBufferDataToColor(int width,
       }
       return;
     case BufferFormat::BGRA_8888:
+      DCHECK_EQ(0, plane);
       for (int y = 0; y < height; ++y) {
         for (int x = 0; x < width; ++x) {
           data[y * stride + x * 4 + 0] = color[2];
@@ -83,6 +88,33 @@ void GLImageTestSupport::SetBufferDataToColor(int width,
         }
       }
       return;
+    case BufferFormat::YUV_420_BIPLANAR: {
+      DCHECK_LT(plane, 2);
+      DCHECK_EQ(0, height % 2);
+      DCHECK_EQ(0, width % 2);
+      // These values are used in the transformation from YUV to RGB color
+      // values. They are taken from the following webpage:
+      // http://www.fourcc.org/fccyvrgb.php
+      uint8_t yuv[] = {
+          (0.257 * color[0]) + (0.504 * color[1]) + (0.098 * color[2]) + 16,
+          -(0.148 * color[0]) - (0.291 * color[1]) + (0.439 * color[2]) + 128,
+          (0.439 * color[0]) - (0.368 * color[1]) - (0.071 * color[2]) + 128};
+      if (plane == 0) {
+        for (int y = 0; y < height; ++y) {
+          for (int x = 0; x < width; ++x) {
+            data[stride * y + x] = yuv[0];
+          }
+        }
+      } else {
+        for (int y = 0; y < height / 2; ++y) {
+          for (int x = 0; x < width / 2; ++x) {
+            data[stride * y + x * 2] = yuv[1];
+            data[stride * y + x * 2 + 1] = yuv[2];
+          }
+        }
+      }
+      return;
+    }
     case BufferFormat::ATC:
     case BufferFormat::ATCIA:
     case BufferFormat::DXT1:
@@ -91,7 +123,6 @@ void GLImageTestSupport::SetBufferDataToColor(int width,
     case BufferFormat::R_8:
     case BufferFormat::RGBA_4444:
     case BufferFormat::UYVY_422:
-    case BufferFormat::YUV_420_BIPLANAR:
     case BufferFormat::YUV_420:
       NOTREACHED();
       return;