Fix test addresses to use uintptr_t instead of u_int64_t.

When a variable is used to set (and lookup) MappingInfo's "start_addr"
field, it needs to match types -- which is "uintptr_t".  When Chrome OS
updated the 'make' that's used for building, the 32-bit "char *" had
sign-extended when cast up to a u_int64_t -- maybe because pointers were
unsigned before and then changed to be signed -- and that caused the address
lookup to fail.

BUG=chromium-os:25355
TEST=Ran Breakpad unittests
A=mkrebs@chromium.org
Review URL: http://breakpad.appspot.com/345001

git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@908 4c0a9323-5329-0410-9bdc-e9ce6186880e

src/client/linux/handler/exception_handler_unittest.cc

@@ -626,7 +626,7 @@ TEST(ExceptionHandlerTest, ModuleInfo) {
                                  MAP_PRIVATE | MAP_ANON,
                                  -1,
                                  0));
-  const u_int64_t kMemoryAddress = reinterpret_cast<u_int64_t>(memory);
+  const uintptr_t kMemoryAddress = reinterpret_cast<uintptr_t>(memory);
   ASSERT_TRUE(memory);
 
   string minidump_filename;