Remove linux coverage scripts.

base/base.gyp

Index: base/base.gyp
diff --git a/base/base.gyp b/base/base.gyp
index 8940c5be9de3c86a11ebb6d6f05142a0d6427598..551aa712027d0a156ce1ddb4bcdaa246071f5a50 100644
--- a/base/base.gyp
+++ b/base/base.gyp
@@ -733,26 +733,6 @@
             # iOS does not use message_pump_libevent.
             ['exclude', '^message_loop/message_pump_libevent_unittest\\.cc$'],
           ],
-          'conditions': [
-            ['coverage != 0', {
-              'sources!': [
-                # These sources can't be built with coverage due to a toolchain
-                # bug: http://openradar.appspot.com/radar?id=1499403
-                'json/json_reader_unittest.cc',
-                'strings/string_piece_unittest.cc',
-
-                # These tests crash when run with coverage turned on due to an
-                # issue with llvm_gcda_increment_indirect_counter:
-                # http://crbug.com/156058
-                'debug/trace_event_unittest.cc',
-                'debug/trace_event_unittest.h',
-                'logging_unittest.cc',
-                'string_util_unittest.cc',
-                'test/trace_event_analyzer_unittest.cc',
-                'utf_offset_string_conversions_unittest.cc',
-              ],
-            }],
-          ],
           'actions': [
             {
               'action_name': 'copy_test_data',