[Instantiation] Ensure new models have modified timestamp

...to avoid https://github.com/nasa/openmct/issues/745#issuecomment-204561163

platform/core/bundle.js

@@ -355,7 +355,8 @@ define([
                     "implementation": InstantiationCapability,
                     "depends": [
                         "$injector",
-                        "identifierService"
+                        "identifierService",
+                        "now"
                     ]
                 }
             ],

platform/core/src/capabilities/InstantiationCapability.js

@@ -35,10 +35,16 @@ define(
          * @param $injector Angular's `$injector`
          * @implements {Capability}
          */
-        function InstantiationCapability($injector, identifierService, domainObject) {
+        function InstantiationCapability(
+            $injector,
+            identifierService,
+            now,
+            domainObject
+        ) {
             this.$injector = $injector;
             this.identifierService = identifierService;
             this.domainObject = domainObject;
+            this.now = now;
         }
 
         /**
@@ -57,6 +63,8 @@ define(
                 space = parsedId.getDefinedSpace(),
                 id = this.identifierService.generate(space);
 
+            model.modified = this.now();
+
             // Lazily initialize; instantiate depends on capabilityService,
             // which depends on all capabilities, including this one.
             this.instantiateFn = this.instantiateFn ||

platform/core/test/capabilities/InstantiationCapabilitySpec.js

@@ -31,6 +31,7 @@ define(
                 mockIdentifierService,
                 mockInstantiate,
                 mockIdentifier,
+                mockNow,
                 mockDomainObject,
                 instantiation;
 
@@ -57,9 +58,13 @@ define(
                 mockIdentifierService.parse.andReturn(mockIdentifier);
                 mockIdentifierService.generate.andReturn("some-id");
 
+                mockNow = jasmine.createSpy();
+                mockNow.andReturn(1234321);
+
                 instantiation = new InstantiationCapability(
                     mockInjector,
                     mockIdentifierService,
+                    mockNow,
                     mockDomainObject
                 );
             });
@@ -81,7 +86,10 @@ define(
                 expect(instantiation.instantiate(testModel))
                     .toBe(mockDomainObject);
                 expect(mockInstantiate)
-                    .toHaveBeenCalledWith(testModel, jasmine.any(String));
+                    .toHaveBeenCalledWith({
+                        someKey: "some value",
+                        modified: mockNow()
+                    }, jasmine.any(String));
             });
 
         });