[kernel] Don't allocate contexts in BinaryPrinter._ensureCanonicalName

When compiling the cfe with an aot-compiled cfe this removes ~43 mb of context allocations in `BinaryPrinter._ensureCanonicalName` and has these changes when benchmarking:

```
msec task-clock:u: -5.0067% +/- 0.6053% (-288.75 +/- 34.91) (5767.31 -> 5478.56)
page-faults:u: 2.7077% +/- 0.1426% (2942.48 +/- 155.01) (108670.96 -> 111613.44)
cycles:u: -5.3274% +/- 0.6265% (-1278360098.44 +/- 150341087.36) (23995901283.80 -> 22717541185.36)
instructions:u: -4.3319% +/- 0.0009% (-1195734804.64 +/- 241700.46) (27602908367.64 -> 26407173563.00)
branch-misses:u: -3.4011% +/- 3.0065% (-3245774.08 +/- 2869267.25) (95434325.44 -> 92188551.36)
seconds time elapsed: -5.0025% +/- 0.6041% (-0.29 +/- 0.03) (5.77 -> 5.48)
seconds user: -5.3148% +/- 0.6838% (-0.29 +/- 0.04) (5.52 -> 5.22)
Scavenge(   new space) goes from 65 to 64
MarkSweep(   promotion) goes from 10 to 9
Evacuate(store buffer) goes from 2 to 1
```

although most of it is probably a happy accident with the GCs.

Compiling the analysis server only gives:

```

page-faults:u: 0.6385% +/- 0.1266% (1058.68 +/- 209.95) (165813.00 -> 166871.68)
instructions:u: -0.0158% +/- 0.0005% (-6794934.20 +/- 222091.71) (42904117069.28 -> 42897322135.08)
Scavenge(   new space) goes from 103 to 101
```
Change-Id: I85ceece0df699bb2393f3ab72fe6130134b49132
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/438681
Reviewed-by: Johnni Winther <[email protected]>
Commit-Queue: Jens Johansen <[email protected]>

Author: jensjoha

pkg/kernel/lib/binary/ast_to_binary.dart

@@ -984,26 +984,27 @@ class BinaryPrinter implements Visitor<void>, BinarySink {
       return canonicalName;
     }
 
-    CanonicalName ensureCanonicalNameForNode(TreeNode? parentNode) {
-      if (parentNode is Component) {
-        return parentNode.root;
-      }
-      if (parentNode is NamedNode) {
-        CanonicalName? canonicalName = parentNode.reference.canonicalName;
-        if (canonicalName != null) {
-          return canonicalName;
-        }
-        CanonicalName parentCanonicalName =
-            ensureCanonicalNameForNode(parentNode.parent);
-        parentNode.bindCanonicalNames(parentCanonicalName);
-        return parentNode.reference.canonicalName!;
-      } else {
-        throw new ArgumentError('Missing canonical name for $reference');
+    _ensureCanonicalName_forNode(reference.node, reference);
+    return reference.canonicalName!;
+  }
+
+  CanonicalName _ensureCanonicalName_forNode(
+      TreeNode? parentNode, Reference reference) {
+    if (parentNode is Component) {
+      return parentNode.root;
+    }
+    if (parentNode is NamedNode) {
+      CanonicalName? canonicalName = parentNode.reference.canonicalName;
+      if (canonicalName != null) {
+        return canonicalName;
       }
+      CanonicalName parentCanonicalName =
+          _ensureCanonicalName_forNode(parentNode.parent, reference);
+      parentNode.bindCanonicalNames(parentCanonicalName);
+      return parentNode.reference.canonicalName!;
+    } else {
+      throw new ArgumentError('Missing canonical name for $reference');
     }
-
-    ensureCanonicalNameForNode(reference.node);
-    return reference.canonicalName!;
   }
 
   void checkCanonicalName(CanonicalName node) {