fix(video-quality): different tooltips for different definitions

lang/main.json

     "videoStatus": {
         "callQuality": "Call Quality",
         "hd": "HD",
+        "hdTooltip": "Viewing high definition video",
         "highDefinition": "High definition",
         "labelTooltipAudioOnly":  "Audio-only mode enabled",
         "labelTooiltipNoVideo": "No video",
         "labelTooltipVideo": "Current video quality",
         "ld": "LD",
+        "ldTooltip": "Viewing low definition video",
         "lowDefinition": "Low definition",
         "onlyAudioAvailable": "Only audio is available",
         "onlyAudioSupported": "We only support audio in this browser.",
         "p2pVideoQualityDescription": "In peer to peer mode, received call quality can only be toggled between high and audio only. Other settings will not be honored until peer to peer is exited.",
         "recHighDefinitionOnly": "Will prefer high definition.",
         "sd": "SD",
+        "sdTooltip": "Viewing standard definition video",
         "standardDefinition": "Standard definition",
         "qualityButtonTip": "Change received video quality"
     },

react/features/video-quality/components/VideoQualityLabel.web.js

             labelContent = <i className = 'icon-visibility-off' />;
             tooltipKey = 'videoStatus.labelTooiltipNoVideo';
         } else {
-            labelContent = this._mapResolutionToTranslation(_resolution);
-            tooltipKey = 'videoStatus.labelTooltipVideo';
+            const translationKeys
+                = this._mapResolutionToTranslationsKeys(_resolution);
+
+            labelContent = t(translationKeys.labelKey);
+            tooltipKey = translationKeys.tooltipKey;
         }
 
 
     }
 
     /**
-     * Matches the passed in resolution with a translation key for describing
+     * Matches the passed in resolution with a translation keys for describing
      * the resolution. The passed in resolution will be matched with a known
      * resolution that it is at least greater than or equal to.
      *
      * @param {number} resolution - The video height to match with a
      * translation.
      * @private
-     * @returns {string}
+     * @returns {Object}
      */
-    _mapResolutionToTranslation(resolution) {
+    _mapResolutionToTranslationsKeys(resolution) {
         // Set the default matching resolution of the lowest just in case a
         // match is not found.
         let highestMatchingResolution = RESOLUTIONS[0];
             }
         }
 
-        return this.props.t(
-            RESOLUTION_TO_TRANSLATION_KEY[highestMatchingResolution]);
+        const labelKey
+            = RESOLUTION_TO_TRANSLATION_KEY[highestMatchingResolution];
+
+        return {
+            labelKey,
+            tooltipKey: `${labelKey}Tooltip`
+        };
     }
 }