Implement Dump-on-DCHECK (via a new LogSeverity).

third_party/WebKit/Source/wtf/AssertionsTest.cpp

Index: third_party/WebKit/Source/wtf/AssertionsTest.cpp
diff --git a/third_party/WebKit/Source/wtf/AssertionsTest.cpp b/third_party/WebKit/Source/wtf/AssertionsTest.cpp
index a15d47cbec802efe12c66c568fa546eaac3c5559..bb4a3ee7d2237fdd73f5a942fe53594ad932b0fb 100644
--- a/third_party/WebKit/Source/wtf/AssertionsTest.cpp
+++ b/third_party/WebKit/Source/wtf/AssertionsTest.cpp
@@ -12,9 +12,14 @@ namespace WTF {
 
 TEST(AssertionsTest, Assertions) {
   ASSERT(true);
-#if DCHECK_IS_ON()
+#if DCHECK_IS_ON() && !defined(DCHECK_IS_DUMP_WITHOUT_CRASH)
   EXPECT_DEATH_IF_SUPPORTED(ASSERT(false), "");
   EXPECT_DEATH_IF_SUPPORTED(ASSERT_NOT_REACHED(), "");
+  EXPECT_DEATH_IF_SUPPORTED(DCHECK_AT(false, __FILE__, __LINE__), "");
+#else
+  ASSERT(false);
+  ASSERT_NOT_REACHED();
+  DCHECK_AT(false, __FILE__, __LINE__);
 #endif
 
   RELEASE_ASSERT(true);
@@ -23,6 +28,8 @@ TEST(AssertionsTest, Assertions) {
   SECURITY_DCHECK(true);
 #if ENABLE(SECURITY_ASSERT)
   EXPECT_DEATH_IF_SUPPORTED(SECURITY_DCHECK(false), "");
+#else
+  SECURITY_DCHECK(false);
 #endif
 
   SECURITY_CHECK(true);