Obsoleted ImGuiCol_ChildWindowBg fix.

And a warning fix.
diff --git a/TextEditor.cpp b/TextEditor.cpp
index 6e669dd..02966f0 100644
--- a/TextEditor.cpp
+++ b/TextEditor.cpp
@@ -994,10 +994,10 @@
 							}
 							else
 							{
-								char buf[2];
-								buf[0] = line[cindex].mChar;
-								buf[1] = '\0';
-								width = ImGui::GetFont()->CalcTextSizeA(ImGui::GetFontSize(), FLT_MAX, -1.0f, buf).x;
+								char buf2[2];
+								buf2[0] = line[cindex].mChar;
+								buf2[1] = '\0';
+								width = ImGui::GetFont()->CalcTextSizeA(ImGui::GetFontSize(), FLT_MAX, -1.0f, buf2).x;
 							}
 						}
 						ImVec2 cstart(textScreenPos.x + cx, lineStartScreenPos.y);
@@ -1124,7 +1124,7 @@
 	mTextChanged = false;
 	mCursorPositionChanged = false;
 
-	ImGui::PushStyleColor(ImGuiCol_ChildWindowBg, ImGui::ColorConvertU32ToFloat4(mPalette[(int)PaletteIndex::Background]));
+	ImGui::PushStyleColor(ImGuiCol_ChildBg, ImGui::ColorConvertU32ToFloat4(mPalette[(int)PaletteIndex::Background]));
 	ImGui::PushStyleVar(ImGuiStyleVar_ItemSpacing, ImVec2(0.0f, 0.0f));
 	if (!mIgnoreImGuiChild)
 		ImGui::BeginChild(aTitle, aSize, aBorder, ImGuiWindowFlags_HorizontalScrollbar | ImGuiWindowFlags_AlwaysHorizontalScrollbar | ImGuiWindowFlags_NoMove);