Increase stack trace depth from 64 to 128.

64 stack frames is not deep enough when destroying an SkSL program:
http://screen/4RFxPFj7TFXRcTF

Change-Id: I53b151a640a982af7864a17ef0381e231e3fb872
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/327338
Auto-Submit: John Stiles <johnstiles@google.com>
Reviewed-by: Mike Klein <mtklein@google.com>
Commit-Queue: John Stiles <johnstiles@google.com>
diff --git a/dm/DM.cpp b/dm/DM.cpp
index a00618b..3de6d5f 100644
--- a/dm/DM.cpp
+++ b/dm/DM.cpp
@@ -355,7 +355,7 @@
         find_culprit();
 
     #if !defined(SK_BUILD_FOR_ANDROID)
-        void* stack[64];
+        void* stack[128];
         int count = backtrace(stack, SK_ARRAY_COUNT(stack));
         char** symbols = backtrace_symbols(stack, count);
         info("\nStack trace:\n");