Don't merge the mappings if their exec bit are different.

src/client/linux/minidump_writer/linux_dumper.cc

Index: src/client/linux/minidump_writer/linux_dumper.cc
diff --git a/src/client/linux/minidump_writer/linux_dumper.cc b/src/client/linux/minidump_writer/linux_dumper.cc
index 43b74ad9de7e4e536e4622aaa21d24705af5a9e0..1572f2722c9b9ebe1c8e20456376ab0a40178695 100644
--- a/src/client/linux/minidump_writer/linux_dumper.cc
+++ b/src/client/linux/minidump_writer/linux_dumper.cc
@@ -354,7 +354,8 @@ bool LinuxDumper::EnumerateMappings() {
             MappingInfo* module = mappings_.back();
             if ((start_addr == module->start_addr + module->size) &&
                 (my_strlen(name) == my_strlen(module->name)) &&
-                (my_strncmp(name, module->name, my_strlen(name)) == 0)) {
+                (my_strncmp(name, module->name, my_strlen(name)) == 0) &&
+                (exec == module->exec)) {
               module->size = end_addr - module->start_addr;
               line_reader->PopLine(line_len);
               continue;