DevTools: Fix the way source map treats single field segment in the very end of mappings.

Source/devtools/front_end/sdk/SourceMap.js

Index: Source/devtools/front_end/sdk/SourceMap.js
diff --git a/Source/devtools/front_end/sdk/SourceMap.js b/Source/devtools/front_end/sdk/SourceMap.js
index 48f8bb493852745b32f9130573f8965e4ec433bb..960bb02ff15ea767afed1c7dff9d0e132ee63c0f 100644
--- a/Source/devtools/front_end/sdk/SourceMap.js
+++ b/Source/devtools/front_end/sdk/SourceMap.js
@@ -269,7 +269,7 @@ WebInspector.SourceMap.prototype = {
             }
 
             columnNumber += this._decodeVLQ(stringCharIterator);
-            if (this._isSeparator(stringCharIterator.peek())) {
+            if (!stringCharIterator.hasNext() || this._isSeparator(stringCharIterator.peek())) {
                 this._mappings.push([lineNumber, columnNumber]);
                 continue;
             }