Prior to this commit, when rendering cookies via `andDo(print())` in
Spring MVC Test, the output for the `MockHttpServletResponse` would
look something like the following:
Cookies = [javax.servlet.http.Cookie@25084a1e]
The reason is that the Cookie class in javax.servlet-api-3.0.1.jar does
not implement toString(). Consequently, nothing about the cookie's
name, value, etc., is displayed, thereby making the debug output for
cookies next to useless.
This commit improves on this by implementing custom toString() logic
for cookies in debug output in Spring MVC Test. For example, the output
now looks like this (without the newlines):
Cookies = [[Cookie@47faa49c name = 'enigma', value = '42', \\
comment = [null], domain = [null], maxAge = -1, \\
path = [null], secure = false, version = 0, \\
httpOnly = false]]
In addition, this commit fixes a minor bug for FlashMap debug output if
the FlashMap is empty.
Issue: SPR-13168
895d43a2b3