Rewrite traverseAllChildren() tests against React.Children API

This function was used in React.Children and Stack.

The corresponding reconciliation functionality is being tested by ReactMultiChild tests.

So we can move these tests to ReactChildren and test its public API.

scripts/fiber/tests-passing-except-dev.txt

@@ -171,11 +171,9 @@ src/renderers/shared/shared/__tests__/ReactCompositeComponent-test.js
 
 src/renderers/shared/shared/__tests__/ReactMultiChild-test.js
 * should warn for duplicated keys with component stack info
+* should warn for using maps as children with owner info
 
 src/renderers/shared/shared/__tests__/ReactStatelessComponent-test.js
 * should warn for childContextTypes on a functional component
 * should warn when given a ref
 * should use correct name in key warning
-
-src/shared/utils/__tests__/traverseAllChildren-test.js
-* should warn for using maps as children with owner info

scripts/fiber/tests-passing.txt

@@ -108,6 +108,15 @@ src/isomorphic/children/__tests__/ReactChildren-test.js
 * should support identity for simple
 * should treat single arrayless child as being in array
 * should treat single child in array as expected
+* should be called for each child
+* should traverse children of different kinds
+* should be called for each child in nested structure
+* should retain key across two mappings
+* should be called for each child in an iterable without keys
+* should be called for each child in an iterable with keys
+* should use keys from entry iterables
+* should not enumerate enumerable numbers (#4776)
+* should allow extension of native prototypes
 * should pass key to returned component
 * should invoke callback with the right context
 * should be called for each child
@@ -122,6 +131,8 @@ src/isomorphic/children/__tests__/ReactChildren-test.js
 * should count the number of children in flat structure
 * should count the number of children in nested structure
 * should flatten children to an array
+* should throw on object
+* should throw on regex
 
 src/isomorphic/children/__tests__/onlyChild-test.js
 * should fail when passed two children
@@ -1536,22 +1547,6 @@ src/shared/utils/__tests__/PooledClass-test.js
 src/shared/utils/__tests__/reactProdInvariant-test.js
 * should throw with the correct number of `%s`s in the URL
 
-src/shared/utils/__tests__/traverseAllChildren-test.js
-* should support identity for simple
-* should treat single arrayless child as being in array
-* should treat single child in array as expected
-* should be called for each child
-* should traverse children of different kinds
-* should be called for each child in nested structure
-* should retain key across two mappings
-* should be called for each child in an iterable without keys
-* should be called for each child in an iterable with keys
-* should use keys from entry iterables
-* should not enumerate enumerable numbers (#4776)
-* should allow extension of native prototypes
-* should throw on object
-* should throw on regex
-
 src/test/__tests__/ReactTestUtils-test.js
 * should have shallow rendering
 * should shallow render a functional component