Auto merge of #14124 - shinglyu:flexbox-trace, r=glennw

Flexbox trace

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This is a follow up for #13740, so r? @jdm

The first patch enables JSON serialization for flexbox flows, the second one fixed format incompatibilities for the layout viewer.

The 3rd and 4th patches are just layout viewer UI enhancements, we could split that to a spearate PR if you prefer.

---
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #13846  (github issue number if applicable).

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- [ ] There are tests for these changes OR
- [x] These changes do not require tests because it's a trivial debug tool

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1 files changed, 5 insertions, 5 deletions

diff --git a/components/layout/flex.rs b/components/layout/flex.rs
index 7b8d694494c..c40c6a1b433 100644
--- a/components/layout/flex.rs
+++ b/components/layout/flex.rs
@@ -35,7 +35,7 @@ use style::values::computed::{LengthOrPercentageOrAutoOrContent, LengthOrPercent
 
 /// The size of an axis. May be a specified size, a min/max
 /// constraint, or an unlimited size
-#[derive(Debug)]
+#[derive(Debug, Serialize)]
 enum AxisSize {
     Definite(Au),
     MinMax(SizeConstraint),
@@ -102,7 +102,7 @@ fn from_flex_basis(flex_basis: LengthOrPercentageOrAutoOrContent,
 
 /// Represents a child in a flex container. Most fields here are used in
 /// flex size resolving, and items are sorted by the 'order' property.
-#[derive(Debug)]
+#[derive(Debug, Serialize)]
 struct FlexItem {
     /// Main size of a flex item, used to store results of flexible length calcuation.
     pub main_size: Au,
@@ -240,7 +240,7 @@ impl FlexItem {
 
 /// A line in a flex container.
 // TODO(stshine): More fields are required to handle collapsed items and baseline alignment.
-#[derive(Debug)]
+#[derive(Debug, Serialize)]
 struct FlexLine {
     /// Range of items belong to this line in 'self.items'.
     pub range: Range<usize>,
@@ -330,7 +330,7 @@ impl FlexLine {
 }
 
 /// A block with the CSS `display` property equal to `flex`.
-#[derive(Debug)]
+#[derive(Debug, Serialize)]
 pub struct FlexFlow {
     /// Data common to all block flows.
     block_flow: BlockFlow,
@@ -496,7 +496,7 @@ impl FlexFlow {
                                       inline_end_content_edge: Au,
                                       content_inline_size: Au) {
         let _scope = layout_debug_scope!("flex::block_mode_assign_inline_sizes");
-        debug!("block_mode_assign_inline_sizes");
+        debug!("flex::block_mode_assign_inline_sizes");
 
         // FIXME (mbrubeck): Get correct mode for absolute containing block
         let containing_block_mode = self.block_flow.base.writing_mode;