Remove inline header includes from non-inline headers (2).

src/isolate.h

Index: src/isolate.h
diff --git a/src/isolate.h b/src/isolate.h
index 0445fbe1ef35c14d8d40ff953e478452f21c2905..bb1fa417b26244136fd47faf537ef0b5d589c81b 100644
--- a/src/isolate.h
+++ b/src/isolate.h
@@ -64,6 +64,7 @@ class HStatistics;
 class HTracer;
 class InlineRuntimeFunctionsTable;
 class InnerPointerToCodeCache;
+class Logger;
 class MaterializedObjectStore;
 class CodeAgingHelper;
 class RegExpStack;