Adding blink gc memory dump infrastructure for thread specific dumps.

Source/platform/heap/Heap.cpp

Index: Source/platform/heap/Heap.cpp
diff --git a/Source/platform/heap/Heap.cpp b/Source/platform/heap/Heap.cpp
index da86dc9910321051af139a72fb216daa19533166..621bb84b897e4f6d3578f44b3cb5ed9df3768c0a 100644
--- a/Source/platform/heap/Heap.cpp
+++ b/Source/platform/heap/Heap.cpp
@@ -34,6 +34,7 @@
 #include "platform/ScriptForbiddenScope.h"
 #include "platform/Task.h"
 #include "platform/TraceEvent.h"
+#include "platform/heap/BlinkGCMemoryDumpProvider.h"
 #include "platform/heap/CallbackStack.h"
 #include "platform/heap/MarkingVisitor.h"
 #include "platform/heap/PageMemory.h"
@@ -41,6 +42,7 @@
 #include "platform/heap/SafePoint.h"
 #include "platform/heap/ThreadState.h"
 #include "public/platform/Platform.h"
+#include "public/platform/WebMemoryAllocatorDump.h"
 #include "wtf/Assertions.h"
 #include "wtf/ContainerAnnotations.h"
 #include "wtf/LeakAnnotations.h"
@@ -213,6 +215,16 @@ void BaseHeap::cleanupPages()
     m_firstPage = nullptr;
 }
 
+void BaseHeap::takeSnapshot(const String& dumpBaseName)
+{
+    size_t pageCount = 0;
+    for (BasePage* page = m_firstPage; page; page = page->next()) {
+        pageCount++;
+    }
+    WebMemoryAllocatorDump* allocatorDump = BlinkGCMemoryDumpProvider::instance()->createMemoryAllocatorDumpForCurrentGC(dumpBaseName);
+    allocatorDump->AddScalar("blink_page_count", "objects", pageCount);
+}
+
 #if ENABLE(ASSERT) || ENABLE(GC_PROFILING)
 BasePage* BaseHeap::findPageFromAddress(Address address)
 {
@@ -1635,10 +1647,15 @@ void Heap::init()
     s_estimatedMarkingTimePerByte = 0.0;
 
     GCInfoTable::init();
+
+    if (Platform::current()->currentThread())
+        Platform::current()->registerMemoryDumpProvider(BlinkGCMemoryDumpProvider::instance());
 }
 
 void Heap::shutdown()
 {
+    if (Platform::current()->currentThread())
+        Platform::current()->unregisterMemoryDumpProvider(BlinkGCMemoryDumpProvider::instance());
     s_shutdownCalled = true;
     ThreadState::shutdownHeapIfNecessary();
 }