Add sharing flag to file open during unsafe image test.

base/memory/shared_memory_unittest.cc

Index: base/memory/shared_memory_unittest.cc
diff --git a/base/memory/shared_memory_unittest.cc b/base/memory/shared_memory_unittest.cc
index cfb0b329e03d1d9be15d977417ca93a7b5e3b8a8..059e0193589a9865ffa61dc6a710fafc3d12326e 100644
--- a/base/memory/shared_memory_unittest.cc
+++ b/base/memory/shared_memory_unittest.cc
@@ -589,8 +589,8 @@ TEST(SharedMemoryTest, UnsafeImageSection) {
   EXPECT_GT(::GetModuleFileName(nullptr, path, arraysize(path)), 0U);
 
   // Map the current executable image to save us creating a new PE file on disk.
-  base::win::ScopedHandle file_handle(
-      ::CreateFile(path, GENERIC_READ, 0, nullptr, OPEN_EXISTING, 0, nullptr));
+  base::win::ScopedHandle file_handle(::CreateFile(
+      path, GENERIC_READ, FILE_SHARE_READ, nullptr, OPEN_EXISTING, 0, nullptr));
   EXPECT_TRUE(file_handle.IsValid());
   base::win::ScopedHandle section_handle(
       ::CreateFileMappingA(file_handle.Get(), nullptr,