[DeclChecker] Skip contextualization of initializers associated with property wrapped variables

Fixes a double-contextualization that results in an assert because
properties with property wrappers have the same initializer in two
places - original property (which becomes computed) and backing
storage property - that's where the initializer is copied.

Contextualization of the fully type-checked initializer should happen
as part of backing storage property processing by the declaration
checker.

Resolves: rdar://163562182

Author: xedin

lib/Sema/TypeCheckDeclPrimary.cpp

@@ -2706,6 +2706,15 @@ class DeclChecker : public DeclVisitor<DeclChecker> {
       if (!PBD->isInitialized(i))
         continue;
 
+      if (PBD->isInitializerSubsumed(i)) {
+        auto *var = PBD->getSingleVar();
+        // The initializer of a property wrapped variable gets transferred
+        // the synthesized backing storage property, let have it contextualized
+        // there.
+        if (var && var->hasAttachedPropertyWrapper())
+          continue;
+      }
+
       if (!PBD->isInitializerChecked(i)) {
         TypeCheckExprOptions options;
 

validation-test/Sema/type_checker_crashers_fixed/rdar163562182.swift

@@ -0,0 +1,34 @@
+// RUN: %target-typecheck-verify-swift
+
+enum CustomError: Error {
+}
+
+struct ValidationError: Error {
+}
+
+func parseOption(_: String) throws -> Int {
+  42
+}
+
+@propertyWrapper
+public struct Option<Value> {
+  public var wrappedValue: Value
+
+  public init(
+    wrappedValue: Value,
+    transform: @Sendable @escaping (String) throws -> Value
+  ) {
+    self.wrappedValue = wrappedValue
+  }
+}
+
+struct Test {
+  @Option(transform: {
+    do {
+      return try parseOption($0)
+    } catch let error as CustomError {
+      throw ValidationError()
+    }
+  })
+  var prop: Int = 0
+}