[debugger] Removed unused GetStepInPositions method

src/runtime/runtime.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_RUNTIME_RUNTIME_H_
 #define V8_RUNTIME_RUNTIME_H_
 
 #include "src/allocation.h"
 #include "src/base/platform/time.h"
 #include "src/objects.h"
@@ skipping 138 matching lines @@
   F(DebugGetProperty, 2, 1)                    \
   F(DebugPropertyTypeFromDetails, 1, 1)        \
   F(DebugPropertyAttributesFromDetails, 1, 1)  \
   F(DebugPropertyIndexFromDetails, 1, 1)       \
   F(DebugNamedInterceptorPropertyValue, 2, 1)  \
   F(DebugIndexedInterceptorElementValue, 2, 1) \
   F(CheckExecutionState, 1, 1)                 \
   F(GetFrameCount, 1, 1)                       \
   F(GetFrameDetails, 2, 1)                     \
   F(GetScopeCount, 2, 1)                       \
-  F(GetStepInPositions, 2, 1)                  \
   F(GetScopeDetails, 4, 1)                     \
   F(GetAllScopesDetails, 4, 1)                 \
   F(GetFunctionScopeCount, 1, 1)               \
   F(GetFunctionScopeDetails, 2, 1)             \
   F(SetScopeVariableValue, 6, 1)               \
   F(DebugPrintScopes, 0, 1)                    \
   F(GetThreadCount, 1, 1)                      \
   F(GetThreadDetails, 2, 1)                    \
   F(SetBreakPointsActive, 1, 1)                \
   F(GetBreakLocations, 2, 1)                   \
@@ skipping 1021 matching lines @@
 
 class DeclareGlobalsEvalFlag : public BitField<bool, 0, 1> {};
 class DeclareGlobalsNativeFlag : public BitField<bool, 1, 1> {};
 STATIC_ASSERT(LANGUAGE_END == 3);
 class DeclareGlobalsLanguageMode : public BitField<LanguageMode, 2, 2> {};
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_RUNTIME_RUNTIME_H_