Add check for Linux minidump ending on bad write for exploitability rating.

src/processor/exploitability_linux.h

Index: src/processor/exploitability_linux.h
===================================================================
--- src/processor/exploitability_linux.h	(revision 1476)
+++ src/processor/exploitability_linux.h	(working copy)
@@ -58,6 +58,12 @@
   // This method checks the exception that triggered the creation of the
   // minidump and reports whether the exception suggests no exploitability.
   bool BenignCrashTrigger(const MDRawExceptionStream *raw_exception_stream);
+
+  // This method checks if the crash occurred during a write to read-only
+  // memory. It does so by checking if the instruction at the instruction
+  // pointer is a write instruction, and if the target of the instruction
+  // is at a spot in memory that prohibits writes.
+  bool EndedOnIllegalWrite(uint64_t instruction_ptr);
 };
 
 }  // namespace google_breakpad