Provide better diffs for object graphs that include objectContaining

Turns this output:
    Expected $[0].foo = Object({ a: 4, b: 5 }) to equal <jasmine.objectContaining(Object({ a: 1, c: 3 }))>.

into this:
    Expected $[0].foo.a = 4 to equal 1.
    Expected $[0].foo.c = undefined to equal 3.

And turns this output:
    Expected spy jasmineDone to have been called with:
       [ ... snipped very long expected call ]
    but actual calls were:
       [ ... snipped very long actual call ]

    Call 0:
      Expected $[0] = Object({ overallStatus: 'failed', totalTime: 1, incompleteReason: undefined, order: Order({ random: true, seed: '88732', sort: Function }), failedExpectations: [ Object({ matcherName: 'toBeResolved', passed: false, message: 'Suite "a suite" ran a "toBeResolved" expectation after it finished.
      Did you forget to return or await the result of expectAsync?', error: undefined, errorForStack: Error, actual: [object Promise], expected: [  ], globalErrorType: 'lateExpeztation' }) ], deprecationWarnings: [  ] }) to equal <jasmine.objectContaining(Object({ failedExpectations: [ <jasmine.objectContaining(Object({ passed: false, globalErrorType: 'lateExpectation', message: 'Suite "a suite" ran a "toBeResolved" expectation after it finished.
      Did you forget to return or await the result of expectAsync?', matcherName: 'toBeResolved' }))> ] }))>.

into this:
    Expected spy jasmineDone to have been called with:
       [ ... snipped very long expected call ]
    but actual calls were:
       [ ... snipped very long actual call ]

    Call 0:
      Expected $[0].failedExpectations[0].globalErrorType = 'lateExpeztation' to equal 'lateExpectation'.

spec/core/asymmetric_equality/ObjectContainingSpec.js

@@ -96,4 +96,65 @@ describe("ObjectContaining", function() {
 
     expect(containing.asymmetricMatch({foo: "fooBar"}, [tester])).toBe(true);
   });
+
+  describe("valuesForDiff_", function() {
+    describe("when other is not an object", function() {
+      it("sets self to jasmineToString()", function () {
+        var containing = new jasmineUnderTest.ObjectContaining({}),
+          result = containing.valuesForDiff_('a');
+
+        expect(result).toEqual({
+          self: '<jasmine.objectContaining(Object({  }))>',
+          other: 'a'
+        });
+      });
+    });
+
+    describe("when other is an object", function() {
+      it("includes keys that are present in both other and sample", function() {
+        var sample = {a: 1, b: 2},
+          other = {a: 3, b: 4},
+          containing = new jasmineUnderTest.ObjectContaining(sample),
+          result = containing.valuesForDiff_(other);
+
+        expect(result.self).not.toBeInstanceOf(jasmineUnderTest.ObjectContaining);
+        expect(result).toEqual({
+          self: sample,
+          other: other
+        });
+      });
+
+      it("includes keys that are present in only sample", function() {
+        var sample = {a: 1, b: 2},
+          other = {a: 3},
+          containing = new jasmineUnderTest.ObjectContaining(sample),
+          result = containing.valuesForDiff_(other);
+
+        expect(result.self).not.toBeInstanceOf(jasmineUnderTest.ObjectContaining);
+        expect(containing.valuesForDiff_(other)).toEqual({
+          self: sample,
+          other: {
+            a: 3,
+            b: undefined
+          }
+        });
+      });
+
+      it("omits keys that are present only in other", function() {
+        var sample = {a: 1, b: 2},
+          other = {a: 3, b: 4, c: 5},
+          containing = new jasmineUnderTest.ObjectContaining(sample),
+          result = containing.valuesForDiff_(other);
+
+        expect(result.self).not.toBeInstanceOf(jasmineUnderTest.ObjectContaining);
+        expect(result).toEqual({
+          self: sample,
+          other: {
+            a: 3,
+            b: 4
+          }
+        });
+      });
+    });
+  });
 });