Increasing the Breakpad stack walker max scan limit from 30 to 40.

src/processor/stackwalker_arm64_unittest.cc

 // Copyright (c) 2010, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 // notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
@@ skipping 331 matching lines @@
     .Append(96, 0)                      // more space
 
     .D64(return_address1)               // actual return address
     // frame 1
     .Mark(&frame1_sp)
     .Append(32, 0)                      // space
 
     .D64(0xF0000000)                    // more junk
     .D64(0x0000000D)
 
-    .Append(256, 0)                     // more space
+    .Append(336, 0)                     // more space
 
     .D64(return_address2)               // actual return address
                                         // (won't be found)
     // frame 2
     .Mark(&frame2_sp)
     .Append(64, 0);                     // end of stack
   RegionFromSection();
 
   raw_context.iregs[MD_CONTEXT_ARM64_REG_PC] = 0x40005510;
   raw_context.iregs[MD_CONTEXT_ARM64_REG_SP] = stack_section.start().Value();
@@ skipping 508 matching lines @@
                           &frame_symbolizer);
   vector<const CodeModule*> modules_without_symbols;
   vector<const CodeModule*> modules_with_corrupt_symbols;
   ASSERT_TRUE(walker.Walk(&call_stack, &modules_without_symbols,
                           &modules_with_corrupt_symbols));
   ASSERT_EQ(0U, modules_without_symbols.size());
   ASSERT_EQ(0U, modules_with_corrupt_symbols.size());
   frames = call_stack.frames();
   ASSERT_EQ(1U, frames->size());
 }