Bug 1319284 - create a WR imageKey from an external texture. r=nical?

add wr_add_external_image_texture() func to create a WR imageKey from an external texture.

MozReview-Commit-ID: DJUsd15EKlw

gfx/webrender_bindings/src/bindings.rs

@@ -470,6 +470,11 @@ pub extern fn wr_add_image(window: &mut WrWindowState, width: u32, height: u32,
     window.api.add_image(width, height, stride_option, format, ImageData::new(bytes))
 }
 
+#[no_mangle]
+pub extern fn wr_add_external_image_texture(window: &mut WrWindowState, width: u32, height: u32, format: ImageFormat, external_image_id: u64) -> ImageKey {
+    window.api.add_image(width, height, None, format, ImageData::External(ExternalImageId(external_image_id)))
+}
+
 #[no_mangle]
 pub extern fn wr_update_image(window: &mut WrWindowState, key: ImageKey, width: u32, height: u32, format: ImageFormat, bytes: * const u8, size: usize) {
     let bytes = unsafe { slice::from_raw_parts(bytes, size).to_owned() };

gfx/webrender_bindings/src/webrender.h

@@ -111,6 +111,17 @@ wr_add_image(wrwindowstate* wrWindow, uint32_t width, uint32_t height,
              uint32_t stride, WRImageFormat format, uint8_t *bytes, size_t size)
 WR_FUNC;
 
+WR_INLINE WRImageKey
+wr_add_external_image_texture(wrwindowstate* wrWindow, uint32_t width, uint32_t height,
+                              WRImageFormat format, uint64_t external_image_id)
+WR_FUNC;
+
+//TODO(Jerry): handle shmem in WR
+//// WR_INLINE WRImageKey
+//// wr_add_external_image_buffer(wrwindowstate* wrWindow, uint32_t width, uint32_t height,
+////                              uint32_t stride, WRImageFormat format, uint8_t *bytes, size_t size)
+//// WR_FUNC;
+
 WR_INLINE void
 wr_update_image(wrwindowstate* wrWindow, WRImageKey key,
                 uint32_t width, uint32_t height,