Fixes misleading error message when compiling dart

editor/tools/compile_analyzer.py

 #!/usr/bin/env python
 # Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 # for details. All rights reserved. Use of this source code is governed by a
 # BSD-style license that can be found in the LICENSE file.
 #
 # Script to compile the analyzer.
 #
 # Usage: compile_analyzer.py OPTIONS files
 #
 
@@ skipping 78 matching lines @@
           print >> output, file,
     print >> output
 
     # version
     print >> output, 'Implementation-Version: %s' % GetDartVersion()
 
 def VerifyJavacGetPath():
   javac_path = GetJavacPath()
   try:
     subprocess.check_output([javac_path, "-version"])
-  except:
+  except (OSError, subprocess.CalledProcessError), e:
     print "You do not have JDK installed, can't build the analyzer"
+    print "Reason: %s" % e
     exit(1)
   return javac_path
-  
+
 def GetJavacPath():
   if 'JAVA_HOME' in os.environ:
     return join(os.environ['JAVA_HOME'], 'bin',
                 'javac' + GetExecutableExtension())
   else:
     return "javac"
 
 def GetJarToolPath():
   if 'JAVA_HOME' in os.environ:
     return join(os.environ['JAVA_HOME'], 'bin', 'jar' + GetExecutableExtension())
@@ skipping 19 matching lines @@
   os.makedirs(options.output_dir)
 
   CopyFiles(options)
   CreateManifestFile(options)
   CompileAnalyzer(options, args)
   CreateJarFile(options)
 
 
 if __name__ == '__main__':
   main()