Fix depth texture sampling on compatibility profile.

gpu/command_buffer/service/gles2_cmd_decoder.cc

Index: gpu/command_buffer/service/gles2_cmd_decoder.cc
diff --git a/gpu/command_buffer/service/gles2_cmd_decoder.cc b/gpu/command_buffer/service/gles2_cmd_decoder.cc
index a97879bdcc9443059501158ada04331afbb4e510..23eebecef9b4794ead34c3ac77bd982a0352b8bf 100644
--- a/gpu/command_buffer/service/gles2_cmd_decoder.cc
+++ b/gpu/command_buffer/service/gles2_cmd_decoder.cc
@@ -5239,10 +5239,20 @@ void GLES2DecoderImpl::DoBindTexture(GLenum target, GLuint client_id) {
       return;
     }
     LogClientServiceForInfo(texture, client_id, "glBindTexture");
+    glBindTexture(target, texture->service_id());
     if (texture->target() == 0) {
       texture_manager()->SetTarget(texture_ref, target);
+      if (!feature_info_->gl_version_info().BehavesLikeGLES() &&
+          feature_info_->gl_version_info().IsAtLeastGL(3, 2)) {
+        // In Desktop GL core profile and GL ES, depth textures are always
+        // sampled to the RED channel, whereas on Desktop GL compatibility
+        // proifle, they are sampled to RED, LUMINANCE, INTENSITY, or ALPHA
+        // channel, depending on the DEPTH_TEXTURE_MODE value.
+        // In theory we only need to apply this for depth textures, but it is
+        // simpler to apply to all textures.
+        glTexParameteri(target, GL_DEPTH_TEXTURE_MODE, GL_RED);
+      }
     }
-    glBindTexture(target, texture->service_id());
   } else {
     glBindTexture(target, 0);
   }