Try fixing virtual memory regression from new tcmalloc: use old kPageShift and kMaxSize w/ kNumClas…

third_party/tcmalloc/chromium/src/common.cc

Index: third_party/tcmalloc/chromium/src/common.cc
diff --git a/third_party/tcmalloc/chromium/src/common.cc b/third_party/tcmalloc/chromium/src/common.cc
index dd175f223692a5adb37048140b30422bae79fe40..32debd9a984109063285f49122be67b3e2975985 100644
--- a/third_party/tcmalloc/chromium/src/common.cc
+++ b/third_party/tcmalloc/chromium/src/common.cc
@@ -58,9 +58,9 @@ static inline int LgFloor(size_t n) {
 
 int AlignmentForSize(size_t size) {
   int alignment = kAlignment;
-  if (size > kMaxSize) {
-    // Cap alignment at kPageSize for large sizes.
-    alignment = kPageSize;
+  if (size > 2048) {
+    // Cap alignment at 256 for large sizes.
+    alignment = 256;
   } else if (size >= 128) {
     // Space wasted due to alignment is at most 1/8, i.e., 12.5%.
     alignment = (1 << LgFloor(size)) / 8;
@@ -69,10 +69,6 @@ int AlignmentForSize(size_t size) {
     // requirements for some SSE types.
     alignment = 16;
   }
-  // Maximum alignment allowed is page size alignment.
-  if (alignment > kPageSize) {
-    alignment = kPageSize;
-  }
   CHECK_CONDITION(size < 16 || alignment >= 16);
   CHECK_CONDITION((alignment & (alignment - 1)) == 0);
   return alignment;