Pass an isolate to RelocInfo

src/assembler.h

Index: src/assembler.h
diff --git a/src/assembler.h b/src/assembler.h
index 163fc3ca49202bab4e0c9ba2b84d8d6ec570ad2f..d5cc4ed216a756bc9f023700af2c2e4114a6992c 100644
--- a/src/assembler.h
+++ b/src/assembler.h
@@ -432,10 +432,13 @@ class RelocInfo {
 
   STATIC_ASSERT(NUMBER_OF_MODES <= kBitsPerInt);
 
-  RelocInfo() {}
+  explicit RelocInfo(Isolate* isolate) : isolate_(isolate) {
+    DCHECK_NOT_NULL(isolate);
+  }
 
-  RelocInfo(byte* pc, Mode rmode, intptr_t data, Code* host)
-      : pc_(pc), rmode_(rmode), data_(data), host_(host) {
+  RelocInfo(Isolate* isolate, byte* pc, Mode rmode, intptr_t data, Code* host)
+      : isolate_(isolate), pc_(pc), rmode_(rmode), data_(data), host_(host) {
+    DCHECK_NOT_NULL(isolate);
   }
 
   static inline bool IsRealRelocMode(Mode mode) {
@@ -518,6 +521,7 @@ class RelocInfo {
   static inline int ModeMask(Mode mode) { return 1 << mode; }
 
   // Accessors
+  Isolate* isolate() const { return isolate_; }
   byte* pc() const { return pc_; }
   void set_pc(byte* pc) { pc_ = pc; }
   Mode rmode() const {  return rmode_; }
@@ -658,6 +662,7 @@ class RelocInfo {
   static const int kApplyMask;  // Modes affected by apply.  Depends on arch.
 
  private:
+  Isolate* isolate_;
   // On ARM, note that pc_ is the address of the constant pool entry
   // to be relocated and not the address of the instruction
   // referencing the constant pool entry (except when rmode_ ==