Add braces to C++ single-line loops and conditionals (NFC) (#2973)

This makes code easier to read and more consistent between C++ and Java.
Also update clang-format settings to always add a line break (even if no braces are used).

wpiutil/src/test/native/cpp/sigslot/signal-threaded.cpp

@@ -45,16 +45,22 @@ namespace {
 
 std::atomic<int> sum{0};
 
-void f(int i) { sum += i; }
+void f(int i) {
+  sum += i;
+}
 
 void emit_many(Signal_mt<int>& sig) {
-  for (int i = 0; i < 10000; ++i) sig(1);
+  for (int i = 0; i < 10000; ++i) {
+    sig(1);
+  }
 }
 
 void connect_emit(Signal_mt<int>& sig) {
   for (int i = 0; i < 100; ++i) {
     auto s = sig.connect_scoped(f);
-    for (int j = 0; j < 100; ++j) sig(1);
+    for (int j = 0; j < 100; ++j) {
+      sig(1);
+    }
   }
 }
 
@@ -68,9 +74,13 @@ TEST(Signal, ThreadedMix) {
   Signal_mt<int> sig;
 
   std::array<std::thread, 10> threads;
-  for (auto& t : threads) t = std::thread(connect_emit, std::ref(sig));
+  for (auto& t : threads) {
+    t = std::thread(connect_emit, std::ref(sig));
+  }
 
-  for (auto& t : threads) t.join();
+  for (auto& t : threads) {
+    t.join();
+  }
 }
 
 TEST(Signal, ThreadedEmission) {
@@ -80,9 +90,13 @@ TEST(Signal, ThreadedEmission) {
   sig.connect(f);
 
   std::array<std::thread, 10> threads;
-  for (auto& t : threads) t = std::thread(emit_many, std::ref(sig));
+  for (auto& t : threads) {
+    t = std::thread(emit_many, std::ref(sig));
+  }
 
-  for (auto& t : threads) t.join();
+  for (auto& t : threads) {
+    t.join();
+  }
 
   ASSERT_EQ(sum, 100000);
 }

wpiutil/src/test/native/cpp/sigslot/signal-tracking.cpp

@@ -45,7 +45,9 @@ namespace {
 
 int sum = 0;
 
-void f1(int i) { sum += i; }
+void f1(int i) {
+  sum += i;
+}
 struct o1 {
   void operator()(int i) { sum += 2 * i; }
 };

wpiutil/src/test/native/cpp/sigslot/signal.cpp

@@ -45,8 +45,12 @@ namespace {
 
 int sum = 0;
 
-void f1(int i) { sum += i; }
-void f2(int i) /*noexcept*/ { sum += 2 * i; }
+void f1(int i) {
+  sum += i;
+}
+void f2(int i) /*noexcept*/ {
+  sum += 2 * i;
+}
 
 struct s {
   static void s1(int i) { sum += i; }