Migrate WTF::HashMap::get() to ::at()

third_party/WebKit/Source/core/css/MediaQueryEvaluator.cpp

Index: third_party/WebKit/Source/core/css/MediaQueryEvaluator.cpp
diff --git a/third_party/WebKit/Source/core/css/MediaQueryEvaluator.cpp b/third_party/WebKit/Source/core/css/MediaQueryEvaluator.cpp
index 95d11abedf982d34adec13b0e0264fd7dd912730..e2b803dde3dd69a305066612dd325f2b024fe6a9 100644
--- a/third_party/WebKit/Source/core/css/MediaQueryEvaluator.cpp
+++ b/third_party/WebKit/Source/core/css/MediaQueryEvaluator.cpp
@@ -817,7 +817,7 @@ bool MediaQueryEvaluator::eval(const MediaQueryExp* expr) const {
 
   // Call the media feature evaluation function. Assume no prefix and let
   // trampoline functions override the prefix if prefix is used.
-  EvalFunc func = gFunctionMap->get(expr->mediaFeature().impl());
+  EvalFunc func = gFunctionMap->at(expr->mediaFeature().impl());
   if (func)
     return func(expr->expValue(), NoPrefix, *m_mediaValues);