Simplify content_layer attachment and viewporting logic.

chrome/browser/android/compositor/scene_layer/static_tab_scene_layer.cc

Index: chrome/browser/android/compositor/scene_layer/static_tab_scene_layer.cc
diff --git a/chrome/browser/android/compositor/scene_layer/static_tab_scene_layer.cc b/chrome/browser/android/compositor/scene_layer/static_tab_scene_layer.cc
index e407884a7012db2d04819abbf18a4eff8fb98f45..03bc6fee789ac5c0f65c9ea635600e5899e00d1e 100644
--- a/chrome/browser/android/compositor/scene_layer/static_tab_scene_layer.cc
+++ b/chrome/browser/android/compositor/scene_layer/static_tab_scene_layer.cc
@@ -57,9 +57,6 @@ void StaticTabSceneLayer::UpdateTabLayer(
     jfloat saturation,
     jfloat brightness) {
   background_color_ = default_background_color;
-  gfx::Size content_viewport_size(content_viewport_width,
-                                  content_viewport_height);
-  gfx::Point content_viewport_offset(content_viewport_x, content_viewport_y);
   if (!content_layer_.get()) {
     android::TabContentManager* tab_content_manager =
         android::TabContentManager::FromJavaObject(jtab_content_manager);
@@ -73,40 +70,13 @@ void StaticTabSceneLayer::UpdateTabLayer(
   bool should_override_content_alpha = last_set_tab_id_ != id;
   last_set_tab_id_ = id;
 
-  // Set up the content layer and move it to the proper position.
-  content_layer_->layer()->SetBounds(gfx::Size(width, height));
-  content_layer_->layer()->SetPosition(gfx::PointF(x, y));
   content_layer_->SetProperties(
       id, can_use_live_layer, static_to_view_blend,
       should_override_content_alpha, content_alpha_override, saturation,
-      gfx::Rect(content_viewport_size), content_viewport_size);
-
-  gfx::Size content_bounds(0, 0);
-  content_bounds = content_layer_->layer()->bounds();
-
-  gfx::Size actual_content_size(content_layer_->GetContentSize());
-
-  bool view_and_content_have_same_orientation =
-      (content_viewport_size.width() > content_viewport_size.height()) ==
-          (actual_content_size.width() > actual_content_size.height()) &&
-      actual_content_size.width() > 0 && actual_content_size.height() > 0 &&
-      content_viewport_size.width() > 0 && content_viewport_size.height() > 0;
-
-  // This may not be true for frames during rotation.
-  bool content_has_consistent_width =
-      actual_content_size.width() == content_bounds.width() &&
-      actual_content_size.width() == content_viewport_size.width();
-
-  if (view_and_content_have_same_orientation ||
-      (content_has_consistent_width && content_layer_->ShowingLiveLayer())) {
-    y += content_offset_y;
-  } else {
-    // If our orientations are off and we have a static texture, or if we have
-    // a live layer of an unexpected width, move the texture in by the
-    // appropriate amount.
-    x += content_viewport_offset.x();
-    y += content_viewport_offset.y();
-  }
+      false, gfx::Rect());
+
+  x += content_viewport_x;

[Changwan Ryu, 2016/12/12 07:38:04]

Probably content_viewport_x is always 0 here. If that is the case, we don't need
to have this line. (Otherwise, I think we may need a comment explaining why
we're only adding viewport_x.)

[aelias_OOO_until_Jul13, 2016/12/13 02:16:05]

OK, removed this addition as you're right it doesn't do anything and is
inconsistent now.

+  y += content_offset_y;

[Changwan Ryu, 2016/12/12 07:38:04]

This is a great reduction. But now we're passing lots of parameters that aren't
used. How about removing the following parameters?

(content_viewport_x)
content_viewport_y
content_viewport_width
content_viewport_height
width
height

[aelias_OOO_until_Jul13, 2016/12/13 02:16:05]

Done.  I also removed content_offset_y and added it to "y" in Java.

 
   content_layer_->layer()->SetPosition(gfx::PointF(x, y));
   content_layer_->layer()->SetIsDrawable(true);