Consistent qualifier ordering.

Change our handful of `constexpr static`s to the much more common
`static constexpr`. It's easier to "follow existing style" when there
aren't two existing styles to copy from, and all else being equal,
"majority wins" :-)

Test: treehugger
Change-Id: Ifbf0f62ab84c9450bf9c2e49e96915c126fd20c4
diff --git a/tests/malloc_test.cpp b/tests/malloc_test.cpp
index 776643d..aa53450 100644
--- a/tests/malloc_test.cpp
+++ b/tests/malloc_test.cpp
@@ -824,7 +824,7 @@
     8, 32, 128, 4096, 32768, 131072, 1024000, 10240000, 20480000, 300000000
   };
 
-  constexpr static size_t kMaxAllocs = 50;
+  static constexpr size_t kMaxAllocs = 50;
 
   for (size_t size : sizes) {
     // If some of these allocations are stuck in a thread cache, then keep
@@ -867,7 +867,7 @@
   SKIP_WITH_HWASAN << "hwasan does not implement mallinfo2";
   static size_t sizes[] = {8, 32, 128, 4096, 32768, 131072, 1024000, 10240000, 20480000, 300000000};
 
-  constexpr static size_t kMaxAllocs = 50;
+  static constexpr size_t kMaxAllocs = 50;
 
   for (size_t size : sizes) {
     // If some of these allocations are stuck in a thread cache, then keep