Move LayerType enum to gfx_trait

The LayerType enum is only used in gfx_traits and layout, so it
shouldn't be defined in msg.  Move the definition to gfx_traits
instead.

Fixes #9220

components/gfx_traits/lib.rs

@@ -22,7 +22,6 @@ pub use paint_listener::PaintListener;
 use azure::azure_hl::Color;
 use euclid::matrix::Matrix4;
 use euclid::rect::Rect;
-use msg::compositor_msg::LayerType;
 use msg::constellation_msg::{Failure, PipelineId};
 use std::fmt::{self, Debug, Formatter};
 
@@ -38,6 +37,18 @@ pub enum LayerKind {
     HasTransform,
 }
 
+#[derive(Clone, PartialEq, Eq, Copy, Hash, Deserialize, Serialize, HeapSizeOf)]
+pub enum LayerType {
+    /// A layer for the fragment body itself.
+    FragmentBody,
+    /// An extra layer created for a DOM fragments with overflow:scroll.
+    OverflowScroll,
+    /// A layer created to contain ::before pseudo-element content.
+    BeforePseudoContent,
+    /// A layer created to contain ::after pseudo-element content.
+    AfterPseudoContent,
+}
+
 /// The scrolling policy of a layer.
 #[derive(Clone, PartialEq, Eq, Copy, Deserialize, Serialize, Debug, HeapSizeOf)]
 pub enum ScrollPolicy {

components/layout/flow.rs

@@ -34,11 +34,10 @@ use flow_list::{FlowList, FlowListIterator, MutFlowListIterator};
 use flow_ref::{self, FlowRef, WeakFlowRef};
 use fragment::{Fragment, FragmentBorderBoxIterator, SpecificFragmentInfo};
 use gfx::display_list::{ClippingRegion, DisplayList};
-use gfx_traits::LayerId;
+use gfx_traits::{LayerId, LayerType};
 use incremental::{RECONSTRUCT_FLOW, REFLOW, REFLOW_OUT_OF_FLOW, RestyleDamage};
 use inline::InlineFlow;
 use model::{CollapsibleMargins, IntrinsicISizes, MarginCollapseInfo};
-use msg::compositor_msg::LayerType;
 use multicol::MulticolFlow;
 use parallel::FlowParallelInfo;
 use rustc_serialize::{Encodable, Encoder};

components/layout/fragment.rs

@@ -17,14 +17,13 @@ use gfx;
 use gfx::display_list::{BLUR_INFLATION_FACTOR, OpaqueNode};
 use gfx::text::glyph::CharIndex;
 use gfx::text::text_run::{TextRun, TextRunSlice};
-use gfx_traits::LayerId;
+use gfx_traits::{LayerId, LayerType};
 use incremental::{RECONSTRUCT_FLOW, RestyleDamage};
 use inline::{FIRST_FRAGMENT_OF_ELEMENT, InlineFragmentContext, InlineFragmentNodeInfo};
 use inline::{InlineMetrics, LAST_FRAGMENT_OF_ELEMENT};
 use ipc_channel::ipc::IpcSender;
 use layout_debug;
 use model::{self, IntrinsicISizes, IntrinsicISizesContribution, MaybeAuto, specified};
-use msg::compositor_msg::LayerType;
 use msg::constellation_msg::PipelineId;
 use net_traits::image::base::Image;
 use net_traits::image_cache_task::UsePlaceholder;

components/msg/compositor_msg.rs

@@ -22,15 +22,3 @@ impl FrameTreeId {
         *u += 1;
     }
 }
-
-#[derive(Clone, PartialEq, Eq, Copy, Hash, Deserialize, Serialize, HeapSizeOf)]
-pub enum LayerType {
-    /// A layer for the fragment body itself.
-    FragmentBody,
-    /// An extra layer created for a DOM fragments with overflow:scroll.
-    OverflowScroll,
-    /// A layer created to contain ::before pseudo-element content.
-    BeforePseudoContent,
-    /// A layer created to contain ::after pseudo-element content.
-    AfterPseudoContent,
-}