Skip deleted object files in POSIX base::debug::StackTrace

The file names read from /proc/self/maps can contain a special " (deleted)"
suffix to indicate that the file has been deleted (unlinked). This is expected
and should not trigger a LOG(WARNING).

Change-Id: Ia96b3bf1894c8fbd6bfa0c217bc8a01bbb59d750
Reviewed-on: https://chromium-review.googlesource.com/1186622Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
Cr-Commit-Position: refs/heads/master@{#586334}

base/debug/stack_trace_posix.cc

@@ -49,6 +49,7 @@
 #include "base/numerics/safe_conversions.h"
 #include "base/posix/eintr_wrapper.h"
 #include "base/strings/string_number_conversions.h"
+#include "base/strings/string_util.h"
 #include "build/build_config.h"
 
 #if defined(USE_SYMBOLIZE)
@@ -690,6 +691,11 @@ class SandboxSymbolizeHelper {
           // Skip pseudo-paths, like [stack], [vdso], [heap], etc ...
           continue;
         }
+        if (base::EndsWith(region.path, " (deleted)",
+                           base::CompareCase::SENSITIVE)) {
+          // Skip deleted files.
+          continue;
+        }
         // Avoid duplicates.
         if (modules_.find(region.path) == modules_.end()) {
           int fd = open(region.path.c_str(), O_RDONLY | O_CLOEXEC);