Fix a number of c++ build errors (#715)

* Move -fvisibility-inlines-hidden from common_flags to cxx_flags

This option isn't supported by C (and causes the build to fail under
at least rodete).

Manifested error was:

```
-- Looking for include file openssl/rand.h
-- Looking for include file openssl/rand.h - not found
CMake Error at core/src/firebase/firestore/util/CMakeLists.txt:94 (message):
  No implementation for SecureRandom available.

-- Configuring incomplete, errors occurred!
```

which is completely misleading. :(

* Fix exception include for std::logic_error

Was causing compiler error on (at least) rodete.

(http://en.cppreference.com/w/cpp/error/logic_error suggests that
stdexcept is the correct header.)

* Remove 'const' from vector contents.

vectors cannot contain const objects as the contained objects are
required to be assignable and copy constructable. (Not *quite* strictly
true; since c++11, this requirement now depends on the operations
performed on the container. But my compiler objects at any rate.)

http://en.cppreference.com/w/cpp/container/vector

https://stackoverflow.com/questions/8685257/why-cant-you-put-a-const-object-into-a-stl-container

* Add brackets as suggested (required) by my compiler.

* Add missing include

For LLONG_MIN, etc.

* Enable gnu extension to c++11 for firestore/util *test*.

We disable them by default (in cmake/CompilerSetup.cmake) but our tests
requires hexidecimal floating point, which is not supported in c++11
(though is supported in C++17, gnu++11, and others).

http://en.cppreference.com/w/cpp/language/floating_literal
https://bugzilla.redhat.com/show_bug.cgi?id=1321986

* Fix printf format for uint64_t

http://en.cppreference.com/w/cpp/types/integer
https://stackoverflow.com/questions/9225567/how-to-print-a-int64-t-type-in-c

* Allow 0 length printf template strings in tests.

* Get rid of a multi line comment.

The backslash is apparently interpreted by the compiler cause the next
line to be ignored too. In this case, the next line is (currently) a
comment, and would be ignored anyways. (But that doesn't stop the
compiler from yelling.)

* Run ./scripts/style.sh

3 files changed, 18 insertions, 12 deletions

diff --git a/Firestore/core/test/firebase/firestore/util/CMakeLists.txt b/Firestore/core/test/firebase/firestore/util/CMakeLists.txt
index eb5a898..93cca16 100644
--- a/Firestore/core/test/firebase/firestore/util/CMakeLists.txt
+++ b/Firestore/core/test/firebase/firestore/util/CMakeLists.txt
@@ -12,6 +12,11 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+set(CMAKE_CXX_EXTENSIONS ON)
+
+# Required to allow 0 length printf style strings for testing purposes.
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-format-zero-length")
+
 if(HAVE_ARC4RANDOM)
   cc_test(
     firebase_firestore_util_arc4random_test
diff --git a/Firestore/core/test/firebase/firestore/util/comparison_test.cc b/Firestore/core/test/firebase/firestore/util/comparison_test.cc
index ecbed4a..ccb3011 100644
--- a/Firestore/core/test/firebase/firestore/util/comparison_test.cc
+++ b/Firestore/core/test/firebase/firestore/util/comparison_test.cc
@@ -16,6 +16,7 @@
 
 #include "Firestore/core/src/firebase/firestore/util/comparison.h"
 
+#include <inttypes.h>
 #include <math.h>
 
 #include <limits>
@@ -84,17 +85,17 @@ TEST(Comparison, DoubleCompare) {
   ASSERT_SAME(Compare<double>(-0, 0));
 }
 
-#define ASSERT_BIT_EQUALS(expected, actual)            \
-  do {                                                 \
-    uint64_t expectedBits = DoubleBits(expected);      \
-    uint64_t actualBits = DoubleBits(actual);          \
-    if (expectedBits != actualBits) {                  \
-      std::string message = StringPrintf(              \
-          "Expected <%f> to compare equal to <%f> "    \
-          "with bits <%llX> equal to <%llX>",          \
-          actual, expected, actualBits, expectedBits); \
-      FAIL() << message;                               \
-    }                                                  \
+#define ASSERT_BIT_EQUALS(expected, actual)                 \
+  do {                                                      \
+    uint64_t expectedBits = DoubleBits(expected);           \
+    uint64_t actualBits = DoubleBits(actual);               \
+    if (expectedBits != actualBits) {                       \
+      std::string message = StringPrintf(                   \
+          "Expected <%f> to compare equal to <%f> "         \
+          "with bits <%" PRIu64 "> equal to <%" PRIu64 ">", \
+          actual, expected, actualBits, expectedBits);      \
+      FAIL() << message;                                    \
+    }                                                       \
   } while (0);
 
 #define ASSERT_MIXED_SAME(doubleValue, longValue)                              \
diff --git a/Firestore/core/test/firebase/firestore/util/log_test.cc b/Firestore/core/test/firebase/firestore/util/log_test.cc
index 46cbc4e..973b174 100644
--- a/Firestore/core/test/firebase/firestore/util/log_test.cc
+++ b/Firestore/core/test/firebase/firestore/util/log_test.cc
@@ -30,7 +30,7 @@ namespace util {
 //
 // You can fix it with:
 //
-//   defaults write firebase_firestore_util_log_apple_test \
+//   defaults write firebase_firestore_util_log_apple_test
 //       /google/firebase/debug_mode NO
 TEST(Log, SetAndGet) {
   LogSetLevel(kLogLevelVerbose);