Send overlay promotion hints from to GLStreamTextureImage.

gpu/GLES2/extensions/CHROMIUM/CHROMIUM_stream_texture_matrix.txt

Index: gpu/GLES2/extensions/CHROMIUM/CHROMIUM_stream_texture_matrix.txt
diff --git a/gpu/GLES2/extensions/CHROMIUM/CHROMIUM_stream_texture_matrix.txt b/gpu/GLES2/extensions/CHROMIUM/CHROMIUM_stream_texture_matrix.txt
index 1744f89588c7a99898c1c7a79e2ae360c21c1c87..21526c75757dc19ac8e5da64b9b6f408d410e159 100644
--- a/gpu/GLES2/extensions/CHROMIUM/CHROMIUM_stream_texture_matrix.txt
+++ b/gpu/GLES2/extensions/CHROMIUM/CHROMIUM_stream_texture_matrix.txt
@@ -23,6 +23,8 @@ Overview
     of a stream texture.  Intended for use with Android SurfaceTexture, which
     doesn't provide the value until the front buffer is latched.
 
+    Also allows hints about whether an image could be promoted to an overlay.
+
 New Procedures and Functions
 
     The command
@@ -44,6 +46,29 @@ New Procedures and Functions
     <transform> Provides an additional transform matrix that is applied
       prior to the the stream texture transformation matrix.
 
+    The command
+
+       void SendOverlayPromotionHintCHROMIUM(

[piman, 2016/12/06 21:40:56]

naming nit: no "Send". The naming logic is that you're setting state, and the gl
names just contain the name of the state you set, not any of "Set" "Send" etc.
See e.g. above, UniformMatrix4fvStreamTextureMatrixCHROMIUM "sets" a uniform
matrix, but we leave "set" out of the name.

[liberato (no reviews please), 2016/12/12 16:44:38]

Done.

+               GLuint texture,
+               GLboolean promotion_hint,
+               GLint display_x,
+               GLint display_y)
+
+    Sends a hint about whether the GLImage bound to texture could be promoted
+    to an overlay or not.
+
+    <texture> is the texture id, which should have a stream texture image bound
+      to it.
+    <promotion_hint> indicates whether the GLImage could be promoted.
+    <display_x> is the x coordinate of the origin of the overlay if the image
+      could be promoted.  Otherwise, it is 0.
+    <display_y> is the y coordinate of the origin of the overlay if the image
+      could be promoted.  Otherwise, it is 0.
+
+
+    If <texture> is not a valid texture, or if it doesn't have a stream texture
+    image bound to it, then no action is taken.
+
 Errors
 
     None.