[gcc] Minor syntactic fixes for older gcc

R=ahaas@chromium.org

Change-Id: Ida5a43f65d09a48cce316185932f6d863b0e58a4
Reviewed-on: https://chromium-review.googlesource.com/1184711Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Ben Titzer <titzer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#55295}

test/cctest/test-api.cc

@@ -19138,7 +19138,8 @@ TEST(GetHeapSpaceStatistics) {
   // Force allocation in LO_SPACE so that every space has non-zero size.
   v8::internal::Isolate* i_isolate =
       reinterpret_cast<v8::internal::Isolate*>(isolate);
-  (void)i_isolate->factory()->TryNewFixedArray(512 * 1024);
+  auto unused = i_isolate->factory()->TryNewFixedArray(512 * 1024);
+  USE(unused);
 
   isolate->GetHeapStatistics(&heap_statistics);
 

test/unittests/base/functional-unittest.cc

@@ -74,7 +74,9 @@ TYPED_TEST(FunctionalTest, EqualToImpliesSameHashCode) {
   this->rng()->NextBytes(values, sizeof(values));
   TRACED_FOREACH(TypeParam, v1, values) {
     TRACED_FOREACH(TypeParam, v2, values) {
-      if (e(v1, v2)) EXPECT_EQ(h(v1), h(v2));
+      if (e(v1, v2)) {
+        EXPECT_EQ(h(v1), h(v2));
+      }
     }
   }
 }
@@ -143,7 +145,9 @@ TYPED_TEST(FunctionalTest, BitEqualToImpliesSameBitHash) {
   this->rng()->NextBytes(&values, sizeof(values));
   TRACED_FOREACH(TypeParam, v1, values) {
     TRACED_FOREACH(TypeParam, v2, values) {
-      if (e(v1, v2)) EXPECT_EQ(h(v1), h(v2));
+      if (e(v1, v2)) {
+        EXPECT_EQ(h(v1), h(v2));
+      }
     }
   }
 }