Pull in the latest PartitionAlloc fixes from upstream.

BUG=pdfium:691

Change-Id: If6f1e200e763827ec640b2b79171f3899ea7927e
Reviewed-on: https://pdfium-review.googlesource.com/4050
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Commit-Queue: Chris Palmer <palmer@chromium.org>

1 files changed, 7 insertions, 2 deletions

diff --git a/third_party/base/allocator/partition_allocator/partition_alloc.cc b/third_party/base/allocator/partition_allocator/partition_alloc.cc
index 9523e78d46..a33d7f1d13 100644
--- a/third_party/base/allocator/partition_allocator/partition_alloc.cc
+++ b/third_party/base/allocator/partition_allocator/partition_alloc.cc
@@ -1061,8 +1061,13 @@ void* PartitionReallocGeneric(PartitionRootGeneric* root,
   // determine it is a win.
   if (actual_new_size == actual_old_size) {
     // Trying to allocate a block of size new_size would give us a block of
-    // the same size as the one we've already got, so no point in doing
-    // anything here.
+    // the same size as the one we've already got, so re-use the allocation
+    // after updating statistics (and cookies, if present).
+    PartitionPageSetRawSize(page, PartitionCookieSizeAdjustAdd(new_size));
+#if DCHECK_IS_ON()
+    // Write a new trailing cookie.
+    PartitionCookieWriteValue(static_cast<char*>(ptr) + new_size);
+#endif
     return ptr;
   }