Auto merge of #15913 - emilio:viewport-size, r=heycam,hiro

Use the proper viewport size for stylo

Reviewed upstream at [bug 1303229](https://bugzil.la/1303229).

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components/layout/block.rs

@@ -713,7 +713,7 @@ impl BlockFlow {
         // infrastructure to make it scrollable.
         let viewport_size =
             LogicalSize::from_physical(self.fragment.style.writing_mode,
-                                       shared_context.viewport_size);
+                                       shared_context.viewport_size());
         let block_size = max(viewport_size.block,
                              self.fragment.border_box.size.block + block_start_margin_value +
                              block_end_margin_value);
@@ -990,7 +990,7 @@ impl BlockFlow {
                 if is_root {
                     let viewport_size =
                         LogicalSize::from_physical(self.fragment.style.writing_mode,
-                                                   layout_context.shared_context().viewport_size);
+                                                   layout_context.shared_context().viewport_size());
                     block_size = max(viewport_size.block, block_size)
                 }
 
@@ -1154,7 +1154,7 @@ impl BlockFlow {
     pub fn explicit_block_containing_size(&self, shared_context: &SharedStyleContext) -> Option<Au> {
         if self.is_root() || self.is_fixed() {
             let viewport_size = LogicalSize::from_physical(self.fragment.style.writing_mode,
-                                                           shared_context.viewport_size);
+                                                           shared_context.viewport_size());
             Some(viewport_size.block)
         } else if self.base.flags.contains(IS_ABSOLUTELY_POSITIONED) &&
                   self.base.block_container_explicit_block_size.is_none() {
@@ -1220,7 +1220,7 @@ impl BlockFlow {
     fn calculate_absolute_block_size_and_margins(&mut self, shared_context: &SharedStyleContext) {
         let opaque_self = OpaqueFlow::from_flow(self);
         let containing_block_block_size =
-            self.containing_block_size(&shared_context.viewport_size, opaque_self).block;
+            self.containing_block_size(&shared_context.viewport_size(), opaque_self).block;
 
         // This is the stored content block-size value from assign-block-size
         let content_block_size = self.fragment.border_box.size.block;
@@ -1354,7 +1354,7 @@ impl BlockFlow {
         if self.is_root() { explicit_content_size = max(parent_container_size, explicit_content_size); }
         // Calculate containing block inline size.
         let containing_block_size = if flags.contains(IS_ABSOLUTELY_POSITIONED) {
-            self.containing_block_size(&shared_context.viewport_size, opaque_self).inline
+            self.containing_block_size(&shared_context.viewport_size(), opaque_self).inline
         } else {
             content_inline_size
         };
@@ -1718,7 +1718,7 @@ impl BlockFlow {
             debug!("Setting root position");
             self.base.position.start = LogicalPoint::zero(self.base.writing_mode);
             self.base.block_container_inline_size = LogicalSize::from_physical(
-                self.base.writing_mode, shared_context.viewport_size).inline;
+                self.base.writing_mode, shared_context.viewport_size()).inline;
             self.base.block_container_writing_mode = self.base.writing_mode;
         }
     }
@@ -2820,7 +2820,7 @@ impl ISizeAndMarginsComputer for AbsoluteNonReplaced {
                                     shared_context: &SharedStyleContext)
                                     -> Au {
         let opaque_block = OpaqueFlow::from_flow(block);
-        block.containing_block_size(&shared_context.viewport_size, opaque_block).inline
+        block.containing_block_size(&shared_context.viewport_size(), opaque_block).inline
     }
 
     fn set_inline_position_of_flow_if_necessary(&self,
@@ -2932,7 +2932,7 @@ impl ISizeAndMarginsComputer for AbsoluteReplaced {
                                     -> MaybeAuto {
         let opaque_block = OpaqueFlow::from_flow(block);
         let containing_block_inline_size =
-            block.containing_block_size(&shared_context.viewport_size, opaque_block).inline;
+            block.containing_block_size(&shared_context.viewport_size(), opaque_block).inline;
         let container_block_size = block.explicit_block_containing_size(shared_context);
         let fragment = block.fragment();
         fragment.assign_replaced_inline_size_if_necessary(containing_block_inline_size, container_block_size);
@@ -2947,7 +2947,7 @@ impl ISizeAndMarginsComputer for AbsoluteReplaced {
                                     shared_context: &SharedStyleContext)
                                     -> Au {
         let opaque_block = OpaqueFlow::from_flow(block);
-        block.containing_block_size(&shared_context.viewport_size, opaque_block).inline
+        block.containing_block_size(&shared_context.viewport_size(), opaque_block).inline
     }
 
     fn set_inline_position_of_flow_if_necessary(&self,

components/layout/multicol.rs

@@ -140,7 +140,7 @@ impl Flow for MulticolFlow {
                     // FIXME: (until column balancing) substract margins/borders/padding
                     LogicalSize::from_physical(
                         self.block_flow.base.writing_mode,
-                        ctx.shared_context().viewport_size,
+                        ctx.shared_context().viewport_size(),
                     ).block
                 }
             }

components/layout_thread/lib.rs

@@ -503,7 +503,6 @@ impl LayoutThread {
 
         LayoutContext {
             style_context: SharedStyleContext {
-                viewport_size: self.viewport_size.clone(),
                 stylist: rw_data.stylist.clone(),
                 running_animations: self.running_animations.clone(),
                 expired_animations: self.expired_animations.clone(),

components/style/animation.rs

@@ -426,7 +426,7 @@ fn compute_style_for_animation_step(context: &SharedStyleContext,
             };
 
             let computed =
-                properties::apply_declarations(context.viewport_size,
+                properties::apply_declarations(context.viewport_size(),
                                                /* is_root = */ false,
                                                iter,
                                                previous_style,

components/style/context.rs

@@ -63,9 +63,6 @@ pub enum QuirksMode {
 /// There's exactly one of these during a given restyle traversal, and it's
 /// shared among the worker threads.
 pub struct SharedStyleContext {
-    /// The current viewport size.
-    pub viewport_size: Size2D<Au>,
-
     /// The CSS selector stylist.
     pub stylist: Arc<Stylist>,
 
@@ -93,6 +90,13 @@ pub struct SharedStyleContext {
     pub default_computed_values: Arc<ComputedValues>,
 }
 
+impl SharedStyleContext {
+    /// Return a suitable viewport size in order to be used for viewport units.
+    pub fn viewport_size(&self) -> Size2D<Au> {
+        self.stylist.device.au_viewport_size()
+    }
+}
+
 /// Information about the current element being processed. We group this together
 /// into a single struct within ThreadLocalStyleContext so that we can instantiate
 /// and destroy it easily at the beginning and end of element processing.

components/style/gecko/media_queries.rs

@@ -94,10 +94,10 @@ impl Device {
         self.viewport_override.as_ref().map(|v| {
             Size2D::new(Au::from_f32_px(v.size.width),
                         Au::from_f32_px(v.size.height))
-        }).unwrap_or_else(|| {
-            // TODO(emilio): Grab from pres context.
-            Size2D::new(Au::from_f32_px(1024.0),
-                        Au::from_f32_px(768.0))
+        }).unwrap_or_else(|| unsafe {
+            // TODO(emilio): Need to take into account scrollbars.
+            Size2D::new(Au((*self.pres_context).mVisibleArea.width),
+                        Au((*self.pres_context).mVisibleArea.height))
         })
     }
 }

components/style/gecko_bindings/bindings.rs

@@ -1373,8 +1373,7 @@ extern "C" {
                                            style: ServoComputedValuesBorrowed,
                                            parent_style:
                                                ServoComputedValuesBorrowedOrNull,
-                                           pres_context:
-                                               RawGeckoPresContextBorrowed,
+                                           set: RawServoStyleSetBorrowed,
                                            result:
                                                RawGeckoComputedKeyframeValuesListBorrowedMut);
 }

components/style/matching.rs

@@ -539,7 +539,7 @@ trait PrivateMatchMethods: TElement {
 
         // Invoke the cascade algorithm.
         let values =
-            Arc::new(cascade(shared_context.viewport_size,
+            Arc::new(cascade(shared_context.viewport_size(),
                              rule_node,
                              inherited_values,
                              layout_parent_style,