Auto merge of #10399 - jdm:pb, r=jdm

Private browsing - Initial steps

Rebase of #10160.

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components/compositing/constellation.rs

@@ -1675,6 +1675,19 @@ impl<LTF: LayoutThreadFactory, STF: ScriptThreadFactory> Constellation<LTF, STF>
         ReadyToSave::Ready
     }
 
+    /// Checks whether the pipeline or its ancestors are private
+    #[allow(dead_code)]
+    fn check_is_pipeline_private(&self, pipeline_id: PipelineId) -> bool {
+        let mut pipeline_id = Some(pipeline_id);
+        while let Some(pipeline) = pipeline_id.and_then(|id| self.pipelines.get(&id)) {
+            if pipeline.is_private {
+                return true;
+            }
+            pipeline_id = pipeline.parent_info.map(|(parent_pipeline_id, _)| parent_pipeline_id);
+        }
+        false
+    }
+
     // Close a frame (and all children)
     fn close_frame(&mut self, frame_id: FrameId, exit_mode: ExitPipelineMode) {
         // Store information about the pipelines to be closed. Then close the

components/compositing/pipeline.rs

@@ -58,6 +58,7 @@ pub struct Pipeline {
     /// animations cause composites to be continually scheduled.
     pub running_animations: bool,
     pub children: Vec<FrameId>,
+    pub is_private: bool,
 }
 
 /// The subset of the pipeline that is needed for layer composition.
@@ -275,6 +276,7 @@ impl Pipeline {
             children: vec!(),
             size: size,
             running_animations: false,
+            is_private: false,
         }
     }
 

components/net_traits/lib.rs

@@ -34,6 +34,7 @@ use hyper::mime::{Attr, Mime};
 use ipc_channel::ipc::{self, IpcReceiver, IpcSender};
 use msg::constellation_msg::{PipelineId};
 use serde::{Deserializer, Serializer};
+use std::sync::mpsc::Sender;
 use std::thread;
 use url::Url;
 use websocket::header;
@@ -407,3 +408,8 @@ pub fn unwrap_websocket_protocol(wsp: Option<&header::WebSocketProtocol>) -> Opt
 /// An unique identifier to keep track of each load message in the resource handler
 #[derive(Clone, PartialEq, Eq, Copy, Hash, Debug, Deserialize, Serialize, HeapSizeOf)]
 pub struct ResourceId(pub u32);
+
+pub enum ConstellationMsg {
+    /// Queries whether a pipeline or its ancestors are private
+    IsPrivate(PipelineId, Sender<bool>),
+}

components/script/dom/htmliframeelement.rs

@@ -124,6 +124,7 @@ impl HTMLIFrameElement {
         let window = window.r();
         let (new_subpage_id, old_subpage_id) = self.generate_new_subpage_id();
         let new_pipeline_id = self.pipeline_id.get().unwrap();
+        let private_iframe = self.privatebrowsing();
 
         self.containing_page_pipeline_id.set(Some(window.pipeline()));
 
@@ -135,6 +136,7 @@ impl HTMLIFrameElement {
             old_subpage_id: old_subpage_id,
             new_pipeline_id: new_pipeline_id,
             sandbox: sandboxed,
+            is_private: private_iframe,
         };
         chan.send(ConstellationMsg::ScriptLoadedURLInIFrame(load_info)).unwrap();
 
@@ -248,6 +250,17 @@ impl HTMLIFrameElement {
                       ReflowQueryType::NoQuery,
                       ReflowReason::IFrameLoadEvent);
     }
+
+    /// Check whether the iframe has the mozprivatebrowsing attribute set
+    pub fn privatebrowsing(&self) -> bool {
+        if self.Mozbrowser() {
+            let element = self.upcast::<Element>();
+            element.has_attribute(&Atom::from("mozprivatebrowsing"))
+        } else {
+            false
+        }
+    }
+
 }
 
 pub trait HTMLIFrameElementLayoutMethods {

components/script_traits/lib.rs

@@ -402,6 +402,8 @@ pub struct IFrameLoadInfo {
     pub new_pipeline_id: PipelineId,
     /// Sandbox type of this iframe
     pub sandbox: IFrameSandboxState,
+    ///  Whether this iframe should be considered private
+    pub is_private: bool,
 }
 
 // https://developer.mozilla.org/en-US/docs/Web/API/Using_the_Browser_API#Events