Capitalize the reason

Author: David Ungar

Sources/SwiftDriver/IncrementalCompilation/DependencyKey.swift

@@ -370,7 +370,7 @@ extension DependencyKey.Designator: Comparable {
 
 // MARK: - InvalidationReason
 extension ExternalDependency {
-  public enum InvalidationReason: String {
+  public enum InvalidationReason: String, CustomStringConvertible {
     case added, changed, testing
     init?(_ graph: ModuleDependencyGraph,
           isNewToTheGraph: Bool ,
@@ -385,5 +385,6 @@ extension ExternalDependency {
       }
       return nil
     }
+    public var description: String { rawValue }
   }
 }

Sources/SwiftDriver/IncrementalCompilation/IncrementalCompilationState.swift

@@ -436,9 +436,10 @@ extension IncrementalCompilationState {
     )
     where Nodes.Element == ModuleDependencyGraph.Node
     {
+      let whyString = why.description.capitalized
       let depString = externalDependency.shortDescription
       for node in nodes {
-        report("\(why): \(depString) -> \(node)")
+        report("\(whyString): \(depString) -> \(node)")
       }
     }
   }