[TestWatchpointMultipleThreads] Use default test executable names.

[sivachandra]

Summary

Android has limits on file name lengths. This commit reduces the names of
the test executables to satisfy these limits.

[chaoren]

test/functionalities/watchpoint/multiple_threads/TestWatchpointMultipleThreads.py

54

Why not just use a.out for every executable. If we enforce this rule, we can avoid similar problems in the future too.

[tberghammer]

test/functionalities/watchpoint/multiple_threads/TestWatchpointMultipleThreads.py

54

I agree with changing all executable names to a.out as the name conflicts are already solved with creating a new directory for each test case

[sivachandra]

Use default exe name of a.out for the test cases.

test/functionalities/watchpoint/multiple_threads/TestWatchpointMultipleThreads.py

class WatchpointForMultipleThreadsTestCase(TestBase):
     def setUp(self):
         # Call super's setUp().
         TestBase.setUp(self)
         # Our simple source filename.
         self.source = 'main.cpp'
         # Find the line number to break inside main().
         self.first_stop = line_number(self.source, '// Set break point at this line')
         # Build dictionary to have unique executable names for each test method.
-        self.exe_name = self.testMethodName
+        self.exe_name = self.testMethodName[len('test_watchpoint_multiple_threads_'):]
         self.d = {'CXX_SOURCES': self.source, 'EXE': self.exe_name}
 
     def hello_multiple_threads(self):
         """Test that lldb watchpoint works for multiple threads."""
         exe = os.path.join(os.getcwd(), self.exe_name)
         self.runCmd("file " + exe, CURRENT_EXECUTABLE_SET)
 
         # Add a breakpoint to set a watchpoint when stopped on the breakpoint.