Fix tests for pub global activate.

sdk/lib/_internal/pub/lib/src/solver/version_solver.dart

Index: sdk/lib/_internal/pub/lib/src/solver/version_solver.dart
diff --git a/sdk/lib/_internal/pub/lib/src/solver/version_solver.dart b/sdk/lib/_internal/pub/lib/src/solver/version_solver.dart
index ec276ea22d0911d0c8185405897348840e056534..8a866ab419c22c0a0ebe5564579d5f2bef536dc1 100644
--- a/sdk/lib/_internal/pub/lib/src/solver/version_solver.dart
+++ b/sdk/lib/_internal/pub/lib/src/solver/version_solver.dart
@@ -275,13 +275,16 @@ class Dependency {
   final String depender;
 
   /// The version of the depender that has this dependency.
-  ///
-  /// This will be `null` when [depender] is the magic "pub itself" dependency.
   final Version dependerVersion;
 
   /// The package being depended on.
   final PackageDep dep;
 
+  /// Whether [depender] is a magic dependency (e.g. "pub itself" or "pub global
+  /// activate").
+  bool get isMagic => depender.contains(" ");
+
+
   Dependency(this.depender, this.dependerVersion, this.dep);
 
   String toString() => '$depender $dependerVersion -> $dep';
@@ -342,9 +345,7 @@ abstract class SolveFailure implements ApplicationException {
     for (var dep in sorted) {
       buffer.writeln();
       buffer.write("- ${log.bold(dep.depender)}");
-      if (dep.dependerVersion != null) {
-        buffer.write(" ${dep.dependerVersion}");
-      }
+      if (!dep.isMagic) buffer.write(" ${dep.dependerVersion}");
       buffer.write(" ${_describeDependency(dep.dep)}");
     }