[base] Simplify ASLR on Windows.

Change-Id: I1cb2eb715646366d516c26b11849955990dcda53
Reviewed-on: https://chromium-review.googlesource.com/558881Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46383}

src/base/platform/platform-cygwin.cc

@@ -143,9 +143,7 @@ static void* RandomizedVirtualAlloc(size_t size, int action, int protection) {
 
   if (protection == PAGE_EXECUTE_READWRITE || protection == PAGE_NOACCESS) {
     // For exectutable pages try and randomize the allocation address
-    for (size_t attempts = 0; base == NULL && attempts < 3; ++attempts) {
-      base = VirtualAlloc(OS::GetRandomMmapAddr(), size, action, protection);
-    }
+    base = VirtualAlloc(OS::GetRandomMmapAddr(), size, action, protection);
   }
 
   // After three attempts give up and let the OS find an address to use.

src/base/platform/platform-win32.cc

@@ -753,9 +753,7 @@ static void* RandomizedVirtualAlloc(size_t size, int action, int protection) {
   if (use_aslr &&
       (protection == PAGE_EXECUTE_READWRITE || protection == PAGE_NOACCESS)) {
     // For executable pages try and randomize the allocation address
-    for (size_t attempts = 0; base == NULL && attempts < 3; ++attempts) {
-      base = VirtualAlloc(OS::GetRandomMmapAddr(), size, action, protection);
-    }
+    base = VirtualAlloc(OS::GetRandomMmapAddr(), size, action, protection);
   }
 
   // After three attempts give up and let the OS find an address to use.