[tools/perf] Explicitly disable state tear down on some benchmarks

We're planning to switch the default of ShouldTearDownStateAfterEachStoryRun
to True; but some benchmarks would not work under that setting.

BUG=640990

Review-Url: https://codereview.chromium.org/2301383002
Cr-Commit-Position: refs/heads/master@{#416383}

tools/perf/benchmarks/memory_infra.py

@@ -61,6 +61,10 @@ class MemoryBenchmarkTop10Mobile(_MemoryInfra):
   def Name(cls):
     return 'memory.top_10_mobile'
 
+  @classmethod
+  def ShouldTearDownStateAfterEachStoryRun(cls):
+    return False
+
   @classmethod
   def ShouldDisable(cls, possible_browser):
     # TODO(crbug.com/586148): Benchmark should not depend on DeskClock app.
@@ -107,6 +111,10 @@ class DualBrowserBenchmark(_MemoryInfra):
   def Name(cls):
     return 'memory.dual_browser_test'
 
+  @classmethod
+  def ShouldTearDownStateAfterEachStoryRun(cls):
+    return False
+
   @classmethod
   def ValueCanBeAddedPredicate(cls, value, is_first_result):
     # TODO(crbug.com/610962): Remove this stopgap when the perf dashboard
@@ -129,6 +137,10 @@ class LongRunningDualBrowserBenchmark(_MemoryInfra):
   def Name(cls):
     return 'memory.long_running_dual_browser_test'
 
+  @classmethod
+  def ShouldTearDownStateAfterEachStoryRun(cls):
+    return False
+
   @classmethod
   def ShouldTearDownStateAfterEachStorySetRun(cls):
     return False