Don't directly iterate over the copyManifest map to generate the copy
commands. Iterating over a map in golang isn't guaranteed to give
consistent order. This causes the apex build rules to be executed even
when there is no source file change.
Fix the issue by creating a sorted list of the key and then iterate over
the list.
Bug: 117453592
Test: m apex.test; m.apex.test nothing is built during the second
build
Change-Id: I329a91ec0b6a34cbe745bf9a9ceb0843b63c200c