[wasm] Remove corpus cleanup code.

In https://chromium-review.googlesource.com/c/505614/ I added code to
the test runner which deletes the old corpus of the wasm fuzzer. It's
time now to remove this code again.

R=machenbach@chromium.org

Change-Id: Ic3b8f7a1f6d725f0bf070b404a75ac37551a07c0
Reviewed-on: https://chromium-review.googlesource.com/519405Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45641}

test/fuzzer/testcfg.py

@@ -32,9 +32,6 @@ class FuzzerTestSuite(testsuite.TestSuite):
     for subtest in FuzzerTestSuite.SUB_TESTS:
       shell = 'v8_simple_%s_fuzzer' % subtest
       for fname in os.listdir(os.path.join(self.root, subtest)):
-        if subtest in ["wasm", "wasm_asmjs"] and fname.endswith(".wasm"):
-          os.remove(os.path.join(self.root, subtest, fname))
-          continue
         if not os.path.isfile(os.path.join(self.root, subtest, fname)):
           continue
         test = testcase.TestCase(self, '%s/%s' % (subtest, fname),