Add support for HAL_PIXEL_FORMAT_YCbCr_420_888

- Add fields to CpuConsumer::LockedBuffer for new information
- New lock methods for GraphicBuffer and GraphicBufferMapper for
  the format

Bug: 8734880
Change-Id: If31f82c62d64b6942cf4cc6e5715585c03273f12
diff --git a/libs/ui/GraphicBuffer.cpp b/libs/ui/GraphicBuffer.cpp
index b9cab85..580788d 100644
--- a/libs/ui/GraphicBuffer.cpp
+++ b/libs/ui/GraphicBuffer.cpp
@@ -174,6 +174,27 @@
     return res;
 }
 
+status_t GraphicBuffer::lockYCbCr(uint32_t usage, android_ycbcr *ycbcr)
+{
+    const Rect lockBounds(width, height);
+    status_t res = lockYCbCr(usage, lockBounds, ycbcr);
+    return res;
+}
+
+status_t GraphicBuffer::lockYCbCr(uint32_t usage, const Rect& rect,
+        android_ycbcr *ycbcr)
+{
+    if (rect.left < 0 || rect.right  > this->width ||
+        rect.top  < 0 || rect.bottom > this->height) {
+        ALOGE("locking pixels (%d,%d,%d,%d) outside of buffer (w=%d, h=%d)",
+                rect.left, rect.top, rect.right, rect.bottom,
+                this->width, this->height);
+        return BAD_VALUE;
+    }
+    status_t res = getBufferMapper().lockYCbCr(handle, usage, rect, ycbcr);
+    return res;
+}
+
 status_t GraphicBuffer::unlock()
 {
     status_t res = getBufferMapper().unlock(handle);