Check that Filter::Factory doesn't crash if SDCH is disabled.

net/filter/filter_unittest.cc

Index: net/filter/filter_unittest.cc
diff --git a/net/filter/filter_unittest.cc b/net/filter/filter_unittest.cc
index 3b912520f82d68a41601cfecaec9fa309357289a..5a6ed6276a74c1d8dd0066defdaf0d544081d840 100644
--- a/net/filter/filter_unittest.cc
+++ b/net/filter/filter_unittest.cc
@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include "net/base/sdch_manager.h"
 #include "net/filter/filter.h"
 #include "net/filter/mock_filter_context.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ -347,4 +348,36 @@ TEST(FilterTest, SupportedMimeGzip) {
   EXPECT_TRUE(encoding_types.empty());
 }
 
+// Check that Filter::Factory doesn't crash if SDCH is disabled.
+TEST(FilterTest, FilterFactoryWithDisabledSDCHSupport) {
+  MockFilterContext filter_context;
+
+  // Disable SDCH support
+  SdchManager::EnableSdchSupport(false);
+  EXPECT_TRUE(SdchManager::Global() == NULL);
+  EXPECT_FALSE(SdchManager::sdch_enabled());
+
+  std::vector<Filter::FilterType> encoding_types;
+  Filter* filter;
+
+  // Adding just GZIP should provide valid filter.
+  encoding_types.clear();
+  encoding_types.push_back(Filter::FILTER_TYPE_GZIP);
+  filter = Filter::Factory(encoding_types, filter_context);
+  ASSERT_TRUE(filter != NULL);
+
+  // Adding just SDCH should provide NULL filter.
+  encoding_types.clear();
+  encoding_types.push_back(Filter::FILTER_TYPE_SDCH);
+  filter = Filter::Factory(encoding_types, filter_context);
+  ASSERT_EQ(NULL, filter);
+
+  // Adding both GZIP and SDCH should provide NULL filter.
+  encoding_types.clear();
+  encoding_types.push_back(Filter::FILTER_TYPE_GZIP);
+  encoding_types.push_back(Filter::FILTER_TYPE_SDCH);
+  filter = Filter::Factory(encoding_types, filter_context);
+  ASSERT_EQ(NULL, filter);
+}
+
 }  // namespace net