[inspector] fixed all shorten-64-to-32 warnings

src/inspector/V8HeapProfilerAgentImpl.cpp

Index: src/inspector/V8HeapProfilerAgentImpl.cpp
diff --git a/src/inspector/V8HeapProfilerAgentImpl.cpp b/src/inspector/V8HeapProfilerAgentImpl.cpp
index 048bba0980ef19424fdb4ce00a816795d007263a..3cc7b2a7df51b1de920b8ca8acb5574d2d8dd654 100644
--- a/src/inspector/V8HeapProfilerAgentImpl.cpp
+++ b/src/inspector/V8HeapProfilerAgentImpl.cpp
@@ -294,7 +294,7 @@ void V8HeapProfilerAgentImpl::getHeapObjectId(ErrorString* errorString,
     return;
 
   v8::SnapshotObjectId id = m_isolate->GetHeapProfiler()->GetObjectId(value);
-  *heapSnapshotObjectId = String16::fromInteger(id);
+  *heapSnapshotObjectId = String16::fromInteger(static_cast<size_t>(id));
 }
 
 void V8HeapProfilerAgentImpl::requestHeapStatsUpdate() {