Revert trunk to bleeding_edge at r12484

src/json-parser.h

Index: src/json-parser.h
diff --git a/src/json-parser.h b/src/json-parser.h
index 8eb4f67f22e1c2a7e6c175d8a0f30e1c5c119062..a4db130e2571bde2fea5d98aed4e572ad492b511 100644
--- a/src/json-parser.h
+++ b/src/json-parser.h
@@ -71,11 +71,11 @@ class JsonParser BASE_EMBEDDED {
   inline void AdvanceSkipWhitespace() {
     do {
       Advance();
-    } while (c0_ == ' ' || c0_ == '\t' || c0_ == '\n' || c0_ == '\r');
+    } while (c0_ == '\t' || c0_ == '\r' || c0_ == '\n' || c0_ == ' ');
   }
 
   inline void SkipWhitespace() {
-    while (c0_ == ' ' || c0_ == '\t' || c0_ == '\n' || c0_ == '\r') {
+    while (c0_ == '\t' || c0_ == '\r' || c0_ == '\n' || c0_ == ' ') {
       Advance();
     }
   }
@@ -563,53 +563,6 @@ Handle<String> JsonParser<seq_ascii>::ScanJsonString() {
     AdvanceSkipWhitespace();
     return Handle<String>(isolate()->heap()->empty_string());
   }
-
-  if (seq_ascii && is_symbol) {
-    // Fast path for existing symbols.  If the the string being parsed is not
-    // a known symbol, contains backslashes or unexpectedly reaches the end of
-    // string, return with an empty handle.
-    uint32_t running_hash = isolate()->heap()->HashSeed();
-    int position = position_;
-    uc32 c0 = c0_;
-    do {
-      if (c0 == '\\') {
-        return SlowScanJsonString<SeqAsciiString, char>(source_,
-                                                        position_,
-                                                        position);
-      }
-      if (c0_ < 0x20) return Handle<String>::null();
-      running_hash = StringHasher::AddCharacterCore(running_hash, c0);
-      position++;
-      if (position >= source_length_) return Handle<String>::null();
-      c0 = seq_source_->SeqAsciiStringGet(position);
-    } while (c0 != '"');
-    int length = position - position_;
-    uint32_t hash = (length <= String::kMaxHashCalcLength)
-        ? StringHasher::GetHashCore(running_hash) : length;
-    Vector<const char> string_vector(
-        seq_source_->GetChars() + position_, length);
-    SymbolTable* symbol_table = isolate()->heap()->symbol_table();
-    uint32_t capacity = symbol_table->Capacity();
-    uint32_t entry = SymbolTable::FirstProbe(hash, capacity);
-    uint32_t count = 1;
-    while (true) {
-      Object* element = symbol_table->KeyAt(entry);
-      if (element == isolate()->heap()->raw_unchecked_undefined_value()) {
-        // Lookup failure.
-        break;
-      }
-      if (element != isolate()->heap()->raw_unchecked_the_hole_value() &&
-          String::cast(element)->IsAsciiEqualTo(string_vector)) {
-        // Lookup success, update the current position.
-        position_ = position;
-        // Advance past the last '"'.
-        AdvanceSkipWhitespace();
-        return Handle<String>(String::cast(element));
-      }
-      entry = SymbolTable::NextProbe(entry, count++, capacity);
-    }
-  }
-
   int beg_pos = position_;
   // Fast case for ASCII only without escape characters.
   do {