Fix the Linux build on Ubuntu 12.04 LTS

This fixes the build, which fails because the initialization values
for an array of struct sigaction cannot be { 0 }.

+ Get rid of warning related to unused return value for ftruncate()

BUG=492
Review URL: https://breakpad.appspot.com/447002

git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1027 4c0a9323-5329-0410-9bdc-e9ce6186880e

src/client/linux/handler/exception_handler.cc

@@ -117,7 +117,7 @@ const int kExceptionSignals[] = {
 };
 const int kNumHandledSignals =
     sizeof(kExceptionSignals) / sizeof(kExceptionSignals[0]);
-struct sigaction old_handlers[kNumHandledSignals] = {0};
+struct sigaction old_handlers[kNumHandledSignals];
 bool handlers_installed = false;
 
 // InstallAlternateStackLocked will store the newly installed stack in new_stack
@@ -524,7 +524,7 @@ bool ExceptionHandler::WriteMinidump() {
     // Reposition the FD to its beginning and resize it to get rid of the
     // previous minidump info.
     lseek(minidump_descriptor_.fd(), 0, SEEK_SET);
-    ftruncate(minidump_descriptor_.fd(), 0);
+    static_cast<void>(ftruncate(minidump_descriptor_.fd(), 0));
   }
 
   // Allow ourselves to be dumped.