[MERGE #5727 @sharmasuraj0123] Fixes #5201: Implemented StringTemplate Caching based on location in source Code.

Merge pull request #5727 from sharmasuraj0123:StringTemplateCaching

Changed the earlier implementation of caching the StringTemplates based
on Raw String Literals to their location in the source code.

Old Behavior:

```js
function getCallsite(c) { return c; }
function getFooCallsite() { return getCallsite`foo`; }
print(getFooCallsite() === getFooCallsite()); // true
print(getCallsite`foo` === getCallsite`foo`); // true
print(getCallsite`foo` === eval('getCallsite`foo`')); // true
```

New Behavior:

```js
function getCallsite(c) { return c; }
function getFooCallsite() { return getCallsite`foo`; }
print(getFooCallsite() === getFooCallsite()); // true
print(getCallsite`foo` === getCallsite`foo`); // false
print(getCallsite`foo` === eval('getCallsite`foo`')); // false
```

Deleted the added mapping that would compare and ensure that the two callsite objects are equal based on their raw String literals.
Now it store every diferent pnode object it comes accross and assigns it a register.

Fixes #5201

Author: sharmasuraj0123

lib/Runtime/ByteCode/ByteCodeEmitter.cpp

@@ -5692,20 +5692,13 @@ void ByteCodeGenerator::RecordAllStringTemplateCallsiteConstants(FuncInfo* funcI
     funcInfo->stringTemplateCallsiteRegisterMap.Map([byteCodeFunction](ParseNodePtr pnode, Js::RegSlot location)
     {
         Js::ScriptContext* scriptContext = byteCodeFunction->GetScriptContext();
-        Js::JavascriptLibrary* library = scriptContext->GetLibrary();
-        Js::RecyclableObject* callsiteObject = library->TryGetStringTemplateCallsiteObject(pnode);
-
-        if (callsiteObject == nullptr)
-        {
-            Js::RecyclableObject* rawArray = ByteCodeGenerator::BuildArrayFromStringList(pnode->AsParseNodeStrTemplate()->pnodeStringRawLiterals, pnode->AsParseNodeStrTemplate()->countStringLiterals, scriptContext);
-            rawArray->Freeze();
-
-            callsiteObject = ByteCodeGenerator::BuildArrayFromStringList(pnode->AsParseNodeStrTemplate()->pnodeStringLiterals, pnode->AsParseNodeStrTemplate()->countStringLiterals, scriptContext);
-            callsiteObject->SetPropertyWithAttributes(Js::PropertyIds::raw, rawArray, PropertyNone, nullptr);
-            callsiteObject->Freeze();
+        
+        Js::RecyclableObject* rawArray = ByteCodeGenerator::BuildArrayFromStringList(pnode->AsParseNodeStrTemplate()->pnodeStringRawLiterals, pnode->AsParseNodeStrTemplate()->countStringLiterals, scriptContext);
+        rawArray->Freeze();
 
-            library->AddStringTemplateCallsiteObject(callsiteObject);
-        }
+        Js::RecyclableObject* callsiteObject = ByteCodeGenerator::BuildArrayFromStringList(pnode->AsParseNodeStrTemplate()->pnodeStringLiterals, pnode->AsParseNodeStrTemplate()->countStringLiterals, scriptContext);
+        callsiteObject->SetPropertyWithAttributes(Js::PropertyIds::raw, rawArray, PropertyNone, nullptr);
+        callsiteObject->Freeze();
 
         byteCodeFunction->RecordConstant(byteCodeFunction->MapRegSlot(location), callsiteObject);
     });

lib/Runtime/ByteCode/ByteCodeSerializer.cpp

@@ -3210,16 +3210,7 @@ class ByteCodeBufferReader
         callsite->SetPropertyWithAttributes(Js::PropertyIds::raw, rawArray, PropertyNone, nullptr);
         callsite->Freeze();
 
-        JavascriptLibrary* library = scriptContext->GetLibrary();
-
-        var = library->TryGetStringTemplateCallsiteObject(callsite);
-
-        if (var == nullptr)
-        {
-            library->AddStringTemplateCallsiteObject(callsite);
-            var = callsite;
-        }
-
+        var = callsite;
         LEAVE_PINNED_SCOPE();
 
         return current;

lib/Runtime/ByteCode/FuncInfo.h

@@ -146,7 +146,7 @@ class FuncInfo
     typedef JsUtil::BaseDictionary<double,Js::RegSlot, ArenaAllocator, PrimeSizePolicy> DoubleRegisterMap;
     DoubleRegisterMap doubleConstantToRegister; // maps double constant to register
 
-    typedef JsUtil::BaseDictionary<ParseNodePtr, Js::RegSlot, ArenaAllocator, PowerOf2SizePolicy, Js::StringTemplateCallsiteObjectComparer> StringTemplateCallsiteRegisterMap;
+    typedef JsUtil::BaseDictionary<ParseNodePtr, Js::RegSlot, ArenaAllocator, PowerOf2SizePolicy> StringTemplateCallsiteRegisterMap;
     StringTemplateCallsiteRegisterMap stringTemplateCallsiteRegisterMap; // maps string template callsite constant to register
 
     Scope *paramScope; // top level scope for parameter default values